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ENCRYPTION

Encryption is the conversion of data into a form, called a cipher text that cannot be easily understood by

unauthorized people. Decryption is the process of converting encrypted data back into its original form, so it can be

understood.

The use of encryption/decryption is as old as the art of communication. In wartime, a cipher, often incorrectly called

a code, can be employed to keep the enemy from obtaining the contents of transmissions. (Technically, a code is a

means of representing a signal without the intent of keeping it secret; examples are Morse code and ASCII.) Simple

ciphers include the substitution of letters for numbers, the rotation of letters in the alphabet, and the "scrambling" of

voice signals by inverting the sideband frequencies. More

Complex ciphers work according to sophisticated computer algorithms that rearrange the data bits in digital signals.

In order to easily recover the contents of an encrypted signal, the correct decryption key is required. The key is an

algorithm that undoes the work of the encryption algorithm. Alternatively, a computer can be used in an attempt to

break the cipher. The more complex the encryption algorithm, the more difficult it becomes to eavesdrop on thecommunications without access to the key.

DDBMS

A distributed database management system('DDBMS') is a software system that permits the management of

a distributed database and makes the distribution transparent to the users. A distributed database is a collection of

multiple, logically interrelated databases distributed over a computer network. Sometimes "distributed database

system" is used to refer jointly to the distributed database and the distributed DBMS.

A DDBMS (distributed database management system) is a centralized application that manages a distributed

database as if it were all stored on the same computer. The DDBMS synchronizes all the data periodically, and in

cases where multiple users must access the same data, ensures that updates and deletes performed on the data at one

location will be automatically reflected in the data stored elsewhere.

DBMS (Database Management System) is a general term for any system used to store, manage, and retrieve from a

collection of data. It can be something as simple as a box of index cards, a collection of computer documents or

spreadsheets, or more commonly a software program designed specifically for managing collections of data. Most

DBMSs today are RDBMSs and most DDBMSs are based on RDBMSs. The RDBMS (Relational DBMS) is based

on a Computer Science concept known as relations. The purpose of the RDBMS is to organize the information

logically (for humans) and to efficiently store and retrieve the information (by computers). Typically, tables are

defined for each class of thing for which data is to be kept.

http://en.wikipedia.org/wiki/Database_management_systemhttp://en.wikipedia.org/wiki/Database_management_systemhttp://en.wikipedia.org/wiki/Software_systemhttp://en.wikipedia.org/wiki/Distributed_databasehttp://whatis.techtarget.com/definition/0,289893,sid9_gci933754,00.htmlhttp://whatis.techtarget.com/definition/0,289893,sid9_gci933754,00.htmlhttp://whatis.techtarget.com/definition/0,289893,sid9_gci933754,00.htmlhttp://whatis.techtarget.com/definition/0,289893,sid9_gci933754,00.htmlhttp://en.wikipedia.org/wiki/Distributed_databasehttp://en.wikipedia.org/wiki/Software_systemhttp://en.wikipedia.org/wiki/Database_management_system

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FTP

File Transfer Protocol is a standard network protocol used to transfer files from one host to another over a TCP-

based network, such as the Internet. FTP is built on client-server architecture and utilizes separate control and data

connections between the client and server.FTP users may authenticate themselves using a clear-text sign-in protocolbut can connect anonymously if the server is configured to allow it.

As a user, you can use FTP with a simple command line interface (for example, from the Windows MS-DOS

Prompt window) or with a commercial program that offers a graphical user interface. Your Web browser can also

make FTP requests to download programs you select from a Web page. Using FTP, you can also update (delete,

rename, move, and copy) files at a server. You need to logon to an FTP server. However, publicly available files are

easily accessed using anonymous FTP.

TOPOLOGY

The physical topology of a network refers to the configuration of cables, computers, and other peripherals. Physical

topology should not be confused with logical topology which is the method used to pass information between

workstations.

There are many types of topologies depending upon their architecture:

Bus Topology Star Topology Ring Topology Mesh Topology Hybrid Topology

TRANSMISSION MEDIA

A transmission medium (plural transmission media) is a material substance that can propagate energy waves. For

example, the transmission medium for sound received by the ears is usually air, but solids and liquids may also act

as transmission media for sound.The term transmission medium also refers to a technical device that employs the

material substance to transmit or guide waves. Thus, an optical fiber or a copper cable is a transmission medium.

A transmission medium can be classified as a:

Linear medium, if different waves at any particular point in the medium can be superposed. Bounded medium, if it is finite in extent, otherwise unbounded medium; Uniform medium or homogeneous medium, if its physical properties are unchanged at different points; Isotropic medium, if its physical properties are the same in different directions.

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DLL

Stands for "Dynamic Link Library". A DLL (.dll) file contains a library of functions and other information that can

be accessed by a Windows program. When a program is launched, links to the necessary .dll files are created. If a

static link is created, the .dll files will be in use as long as the program is active. If a dynamic link is created, the .dllfiles will only be used when needed. Dynamic links help programs use resources, such as memory and hard drive

space, more efficiently.

DLL files can also be used by more than one program. In fact, they can even be used by multiple programs at the

same time. Some DLLs come with the Windows operating system while others are added when new programs are

installed. You typically don't want to open a .dll file directly, since the program that uses it will automatically load it

if needed. Though DLL filenames usually end in ".dll," they can also end in .exe, .drv, and .fon, just to make things

more confusing.

THRASHING

If the number offrames allocated to a low priority process is lower than the minimum number required by the

computer architecture then in this case we must suspend the execution of this low priority process. After this we

should page out all of its remaining pages and freeing all of its allocated frames. This provision introduces a swap

in, swap-out level of intermediate CPU scheduling. Let take a example of a process that does not have enough

number offrames. If the process does not have the number offrames it needs to support pages in active use, it

will quickly page fault. The only option remains here for process is to replace some active pages with the page that

requires a frame. However, since all of its pages are in active use, It must replace a page that will be needed againright away. Consequently, it quickly faults again and again that mean replacing pages that it must bring back in

immediately. This high paging activity is called Thrashing. Or we can say that a process is Thrashing if it is

spending more time in paging then executing. Thrashing results in severe performance problems.

If the number of frames allocated to a low priority process is lower than the minimum number required by the

computer architecture then in this case we must suspend the execution of this low priority process. After this we

should page out all of its remaining pages and freeing all of its allocated frames. This provision introduces a swap

in, swap-out level of intermediate CPU scheduling. Let take a example of a process that does not have enough

number of frames.

DATA MINING

Data mining (the analysis step of the Knowledge Discovery in Databases process, or KDD), a relatively young and

interdisciplinary field of computer science is the process of discovering new patterns from large data sets involving

methods from statistics and artificial intelligence but also database management. In contrast to for example machine

learning, the emphasis lies on the discovery ofpreviously unknown patterns as opposed to

generalizing known patterns to new data. Generally, data mining (sometimes called data or knowledge discovery) is

the process of analyzing data from different perspectives and summarizing it into useful information - information

that can be used to increase revenue, cuts costs, or both. Data mining software is one of a number of analytical tools

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for analyzing data. It allows users to analyze data from many different dimensions or angles, categorize it, and

summarize the relationships identified. Technically, data mining is the process of finding correlations or patterns

among dozens of fields in large relational databases.

INTERPRETER

It is the facilitating of oral or sign-language communication, either simultaneously or consecutively, between users

of different languages. The process is described by both the words interpreting and interpretation. In professional

parlance, interpreting denotes the facilitating of communication from one language form into its equivalent, or

approximate equivalent, in another language form; while interpretation denotes the actual product of this work, that

is, the message thus rendered into speech, sign language, writing, non-manual signals, or other language form. This

important distinction is observed in order to avoid confusion. An interpreter is a person who converts a thought or

expression in a source language into an expression with a comparable meaning in a target language in "real time".The interpreter's function is to convey every semantic element (tone and register) and every intention and feeling of

the message that the source-language speaker is directing to target-language recipients.

TWISTED PAIR CABLE

Twisted pair cabling is a type of wiring in which two conductors (the forward and return conductors of a

single circuit) are twisted together for the purposes of canceling out electro magnetic interference (EMI) from

external sources; for instance, electromagnetic radiation from unshielded twisted pair (UTP) cables,and crosstalkbetween neighboring pairs. It was invented by Alexander Graham Bell.

A type of cable that consists of two independently insulated wires twisted around one another. The use of two wires

twisted together helps to reduce crosstalkand electromagnetic induction. While twisted-pair cable is used by older

telephone networks and is the least expensive type oflocal-area network (LAN) cable, most networks contain some

twisted-pair cabling at some point along the network. Other types of cables used for LANs include coaxial

cables and fiber optic cables.

ASYNCHRONOUS TRANSMISSION

In Asynchronous transmission, data is transmitted character by character at irregular intervals. That is, a sendersends a character at any convenient manner and receiver accepts it.

For instance, transmission of data from a terminal to a computer is asynchronous because during data entry byan operator, time between successive keystrokes varies.

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To enable a receiver to recognize a character when it arrives, a transmitter frames each character by putting astart bit before it and one or two( depending upon system) stop bits after it.

Asynchronous transmission is well suited to many input devices. Its advantage is that it does not require anylocal storage at sender or receiver end, because transmission takes place character by character. Hence, it is

cheaper to implement.

CENTRALIZATION

The process of transferring and assigning decision-making authority to higher levels of an organizationalhierarchy.

In a centralized organization, the decision-making has been moved to higher levels or tiers of the organization,such as a head office, or a corporate center.

Knowledge, information and ideas are concentrated at the top, and decisions are cascaded down theorganization.

The span of control of top managers is relatively broad, and there are relatively many tiers in the organization.

TCP/IP

TCP- (Transmission Internet Protocol) is responsible for verifying the correct delivery of data from client to server.

Data can be lost in the intermediate network. TCP adds support to detect errors or lost data and to trigger

retransmission until the data is correctly and completely received.

IP- (Internet protocol) is responsible for moving packet of data from node to node. IP forwards each packet based on

a four byte destination address (the IP number). The Internet authorities assign ranges of numbers to different

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organizations. The organizations assign groups of their numbers to departments. IP operates on gateway machines

that move data from department to organization to region and then around the world.

BATCH FILE

A batch file is a type of script that contains a list of commands. These commands are executed in sequence and can

be used to automate processes. For example, some programs may include a batch file that executes a number of

commands as the program starts up. A user can also create a custom batch file to automate tedious processes such as

copying multiple directories or renaming several files at once.

Batch files are run by the COMMAND.COM program, which is part of DOS and Windows. Therefore, batch files

can only be run within the Windows operating system. Macintosh and Unix have other scripting tools, such as

AppleScript and Unix shell commands, that can be used for similar tasks. Because batch files contain executable

commands, it is important not to open unknown batch files on your hard disk or in e-mail attachments.

CACHE MEMORY

Cache memory is a high speed memory buffer that temporarily stores data that processor needs. It stores random

data usually stores on the first in first out basis. It enables the processor to continue working either at full speed.

Cache memory is basically made up of static RAM integrated into the processor. In static RAM binary values are

stored using flip flops and logic gates. It holds its data until the power is supplied.

Cache memory is usually placed between the processor and the main memory. Basically the main function of the

cache memory is to accelerate your computer. Cache is a technology based on the memory subsystem of your

computer. Caching allows you to do your computer tasks more rapidly. The value of cache is that it is much faster

than the normal memory. The data is searched on the basis of address.

There are two types of cache memory that is level 1 and level 2. Level 1 is memory that is of very high speed

and can be accessed easily with the zero wait state. If the required data or instruction is not present on the level1

then level 2 is tried next. Today level 1 cache memory is mostly implemented within the processor, with level 2

referring to cache memory on motherboard. Nowadays, level2 cache is also becoming available on processor.

BIT RATE

Bit rate, as the name implies, describes the rate at which bits are transferred from one location to another. In other

words, it measures how much data is transmitted in a given amount of time. Bit rate is commonly measured in bits

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per second (bps), kilobits per second (Kbps), or megabits per second (Mbps). For example, a DSL connection may

be able to download data at 768 kbps, while a Fire wire 800 connection can transfer data up to 800 Mbps.

Bit rate can also describe the quality of an audio or video file. For example, an MP3 audio file that is compressed at

192 Kbps will have a greater dynamic range and may sound slightly more clear than the same audio file compressed

at 128 Kbps. This is because more bits are used to represent the audio data for each second of playback. Similarly, a

video file that is compressed at 3000 Kbps will look better than the same file compressed at 1000 Kbps. Just like the

quality of an image is measured in resolution, the quality of an audio or video file is measured by the bit rate.

STACK

In computer science, a stack is a last in, first out (LIFO) abstract data type and data structure. A stack can have any

abstract data type as an element, but is characterized by only three fundamental operations:push,pop and stack top.

The push operation adds a new item to the top of the stack, or initializes the stack if it is empty. If the stack is full

and does not contain enough space to accept the given item, the stack is then considered to be in an overflow state.

The pop operation removes an item from the top of the stack. A pop either reveals previously concealed items, or

results in an empty stack, but if the stack is empty then it goes into underflow state (It means no items are present in

stack to be removed). The stack top operation gets the data from the top-most position and returns it to the user

without deleting it. The same underflow state can also occur in stack top operation if stack is empty.

A stack is a restricted data structure, because only a small number of operations are performed on it. The nature of

the pop and push operations also means that stack elements have a natural order. Elements are removed from the

stack in the reverse order to the order of their addition: therefore, the lower elements are those that have been on the

stack the longest.[1]

Representation of stack

RASTERGRAPHIC

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Most images you see on your computer screen are raster graphics. Pictures found on the Web and photos you import

from your digital camera are raster graphics. They are made up of grid of pixels, commonly referred to as a bitmap.

The larger the image, the more disk space the image file will take up. For example, a 640 x 480 image requires

information to be stored for 307,200 pixels, while a 3072 x 2048 image (from a 6.3 Megapixel digital camera) needs

to store information for a whopping 6,291,456 pixels.

Since raster graphics need to store so much information, large bitmaps require large file sizes. Fortunately, there areseveral image compression algorithms that have been developed to help reduce these file sizes. JPEG and GIF are

the most common compressed image formats on the Web, but several other types of image compression are

available.

Raster graphics can typically be scaled down with no loss of quality, but enlarging a bitmap image causes it to look

blocky and pixilated. For this reason, vector graphics are often used for certain images, such as company logos,

which need to be scaled to different sizes.

GOPHER

A system that pre-dates the World Wide Web for organizing and displaying files on Internet servers. A Gopher

server presents its contents as a hierarchically structured list of files. With the ascendance of the Web, many gopher

databases were converted to Web sites which can be more easily accessed via Web search engines.

The Gopher protocol is a TCP/IP application layer protocol designed for distributing, searching, and retrieving

documents over the Internet .Strongly oriented towards a menu-document design, the Gopher protocol was a

predecessor of (and later, an alternative to) the World Wide Web.

DECENTRALIZATION

The process of transferring and assigning decision-making authority to lower levels of an organizational hierarchy.

In a decentralized organization, the decision-making has been moved to lower levels or tiers of the organization,

such as divisions, branches, departments or subsidiaries.

Knowledge, information and ideas are flowing from the bottom to the top of the organization. The span of control of

top managers is relatively small, and there are relatively few tiers in the organization, because there is more

autonomy in the lower ranks.

COMPUTERGRAPHICS

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The term computer graphics has been used in a broad sense to describe "almost everything on computers that is not

text or sound. Typically, the term computer graphics refers to several different things:

The representation and manipulation of Image Data by a computer. The various technologies used to create and manipulate images. The images so produced, and The sub-field of computer science which studies methods for digitally synthesizing and manipulating visualcontentComputer generated imagery can be categorized into several different types: 2D, 3D, and animated graphics. As

technology has improved, 3D computer graphics have become more common, but 2D computer graphics are still

widely used. Computer graphics has emerged as a sub-field of computer science which studies methods for digitally

synthesizing and manipulating visual content.

VIRTUALMEMORY

In computing, virtual memory is a memory management technique developed for multitasking Kernals. This

technique virtualizes a computer architectures various forms of computer data storage(such as random access

memory and Disk storage), allowing a program to be designed as though there is only one kind of memory, "virtual"

memory, which behaves like directly addressable read/write memory (RAM).

Systems that employ virtual memory:

Use hardware memory more efficiently than do systems without virtual memory. Make the programming of applications easier: By hiding fragmentation. By delegating to the kernel the burden of managing the memory hierarchy.

Zip

Windows users will see this term a lot when looking for files on the Internet. A zip file (.zip) is a "zipped" or

compressed file. For example, when you download a file, if the filename looks like this: "filename.zip," you are

downloading a zipped file. "Zipping" a file involves compressing one or more items into a smaller archive. A zipped

file takes up less hard drive space and takes less time to transfer to another computer. This is why most Windows

files that you find on the Internet are compressed.

To use a zipped file, you'll need to unzip it first. PKZIP for DOS, or WinZip for Windows, are some popular

programs that can unzip files for you. Fortunately, these programs can be downloaded for free from Web sites like

Download.com.

The term "Zip" also refers to a product by Iomega. The company makes a removable storage device called a Zip

Drive. Depending on the model, these drives can hold 100, 250 or 750 MB Zip disks. They are usually used for

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backup and for transferring large files to different locations. However, Zip drives are not as fast as hard drives, so it

is usually not a good idea to run programs off them.

404 ERROR

A 404 error is a common website error message that indicates a webpage cannot be found. It may be produced when

a user clicks an outdated (or "broken") link or when a URL is typed incorrectly in a Web browser's address field.

Some websites display custom 404 error pages, which may look similar to other pages on the site. Other websites

simply display the Web server's default error message text, which typically begins with "Not Found." Regardless of

the appearance, a 404 error means the server is up and running, but the webpage or path to the webpage is not valid.

So why call it a "404 error" instead of simply a "Missing Webpage Error?" The reason is that 404 is an error code

produced by the Web server when it cannot find a webpage. This error code is recognized by search engines, which

helps prevent search engine crawlers from indexing bad URLs. 404 errors can also be read by Web scripts and

website monitoring tools, which can help web masters, locate and fix broken links.

Other common Web server codes are 200, which means a webpage has been found, and 301, which indicates a file

has moved to a new location. Like 404 errors, these status messages are not seen directly by users, but they are used

by search engines and website monitoring software.

SOFTWAREENGINEERING

Software Engineering (SE) is a profession dedicated to designing, implementing, and modifying software so that it

is of high quality, affordable, maintainable, and fast to build. It is a "systematic approach to the analysis, design,assessment, implementation, test, maintenance and reengineering of software, that is, the application of engineering

to software." The term software engineering first appeared in the 1968 NATO Software Engineering Conference.

It is the application of Engineering to software because it integrates significant mathematics, computer science and

practices whose origins are in Engineering.

SOFTWARETESTING

Software testing is an investigation conducted to provide stakeholders with information about the quality of theproduct or service under test. Software testing can also provide an objective, independent view of the software to

allow the business to appreciate and understand the risks of software implementation. Test techniques include, but

are not limited to, the process of executing a program or application with the intent of finding software bugs (errors

or other defects).

Software testing can be stated as the process of validating and verifying that a software program/application/product:

Meets the requirements that guided its design and development;

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Works as expected; and Can be implemented with the same characteristics.Software testing, depending on the testing method employed, can be implemented at any time in the development

process. However, most of the test effort occurs after the requirements have been defined and the coding process has

been completed. As such, the methodology of the test is governed by the software development methodology

adopted.

COMPILER

A compiler is a computer program (or set of programs) that transforms source code written in a programming

language (the source language) into another computer language (the target language, often having a binary form

known as object code.) The most common reason for wanting to transform source code is to create an executable

program.

The name "compiler" is primarily used for programs that translate source code from a high-level programminglanguage to a lower level language (e.g., assembly language or machine code). If the compiled program can run on a

computer whose CPU or operating system is different from the one on which the compiler runs, the compiler is

known as a cross-compiler.

A compiler is likely to perform many or all of the following operations: lexical analysis, preprocessing, parsing,

semantic analysis (Syntax-directed translation), code generation, and code optimization.

ATM

Stands for "Asynchronous Transfer Mode". Most people know of ATMs as automated teller machines -- those

friendly boxes that allow you to withdraw cash from your bank or credit account while charging you a ridiculous

surcharge for the service. In the computer world, however, ATM has a different meaning. Asynchronous Transfer

Mode is a networking technology that transfers data in packets or cells of a fixed size.

ATM uses 53-byte cells (5 bytes for the address header and 48 bytes for the data). These extremely small cells can

be processed through an ATM switch (not an automated teller machine) fast enough to maintain data transfer speeds

of over 600 mbps. The technology was designed for the high-speed transmission of all forms of media from basic

graphics to full-motion video. Because the cells are so small, ATM equipment can transmit large amounts of data

over a single connection while ensuring that no single transmission takes up all the bandwidth. It also allows Internet

Service Providers (ISPs) to assign limited bandwidth to each customer. While this may seem like a downside for the

customer, it actually improves the efficiency of the ISP's Internet connection, causing the overall speed of theconnection to be faster for everybody.

BATCHFILE

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A batch file is a type of script that contains a list of commands. These commands are executed in sequence and can

be used to automate processes. For example, some programs may include a batch file that executes a number of

commands as the program starts up. A user can also create a custom batch file to automate tedious processes such as

copying multiple directories or renaming several files at once.

Batch files are run by the COMMAND.COM program, which is part of DOS and Windows. Therefore, batch files

can only be run within the Windows operating system. Macintosh and Unix have other scripting tools, such asAppleScript and Unix shell commands, that can be used for similar tasks. Because batch files contain executable

commands, it is important not to open unknown batch files on your hard disk or in e-mail attachments.

DATATRANSFERRATE

The data transfer rate is commonly used to measure how fast data is transferred from one location to another. For

example, a hard drive may have a maximum data transfer rate of 480 Mbps, while your ISP may offer an Internet

connection with a maximum data transfer rate of only 1.5 Mbps.

Data transfer rates are typically measured in bits per second (bps) as opposed to bytes per second, which can be

understandably confusing. Because there are eight bits in a byte, a sustained data transfer rate of 80 Mbps is only

transferring 10MB per second. While this is confusing for consumers, Internet service providers must enjoy

measuring data transfer rates in bps since it makes their Internet access speeds sound 8 x faster than they really are.

EXTRANET

Extranets are networks that connect companies with customers and partners. In Extranet a company has to work with the other like-minded organizations on the network, so that it is

accessible to specific people or groups outside the organization.

Extranets require more security and technical consideration because they have to send private informationsecurely over public networks.

Extranets provides a safe way to allow transactional business-to-business activities. Extranet is more complex and costly to set up and requires efficient internal systems.

Example of Extranet:-

Different banks are providing the facility of ATM (Automatic Teller Machine) cards with VISA facility means one

can make use of HDFC ATM in ICICI ATM machine anywhere in the world.

ANDROID

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Android is a mobile operating system developed by Google. It is used by several Smartphones such as the Motorola

Droid, the Samsung Galaxy, and Google's own Nexus One.

The Android operating system (OS) is based on the open Linux kernel, unlike the iPhone OS, Android is open

source, meaning developers can modify and customize the OS for each phone. Therefore, different Android-based

phones may have different graphical user interfaces GUIs even though they use the same OS.

Android phones typically come with several built-in applications and also support third-party programs. Developers

can create programs for Android using the free Android SDK (Software Developer Kit). Android programs are

written in Java and run through Google's "Davlik" virtual machine, which is optimized for mobile devices. Users can

download Android "apps" from the online Android Market.

RELATIONALDATABASE

The Relational model was first introduces by Dr. Edgar Frank Codd, an oxford-trained Mathematician, while

working in IBM Research Centre in 1970s. He represented this idea in a classical paper (A Relational Model of

Data for Large Shared Data banks) and attracted immediate attention due to its simplicity and mathematical

foundations. The Relational model is considered one of the most popular developments in the database technology

because it can be used for representing most of the real world objects and the relationships between them.

Relational Model Terminology

Relation Table

Tuple Row, Record

Attribute Column, Field

Domain Set of Legal Values

Cardinality Number of Rows

Degree Number of Columns

Primary Key Unique Identifier

Foreign Key Identifier used to reference another table

DISTRIBUTEDDATABASE

A Distributed database is a single logical database that is spread physically across computers in multiplelocations that are connected by a data communication links.

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In distributed database the user at any location can access data anywhere in the network as if the data were allstored at the users own location.

The software that manages the distributed database and provides an access mechanism that makes thisdistribution transparent to the user is known as Distributed Database. Management System (DDBMS):- By

the term transparent we mean that the user will be aware of one relational database schema, it doesnt matter

where the data is located or how the query is executed.

C/C++

C is a high-level programming language that was developed in the mid-1970s. It was originally used for writing

UNIX programs, but is now used to write applications for nearly every available platform. Compared to most

previous languages, C is easier to read, more flexible (can be used for a wide variety of purposes), and more

efficient at using memory.

C++, pronounced "C plus," is a programming language that was built off the C language. The syntax of C++ is

nearly identical to C, but it has object-oriented features, which allow the programmer to create objects within the

code. This makes programming easier, more efficient, and some would even say more fun. Because of the power

and flexibility of the language, most software programs today are written in C++.

BUSINESSTOBUSINESS(B2B)

B2B is one of the most important terms in the IT world. B2B is any business process between two companies that uses digital technology. That provides information,

facilitate transactions, execute transactions and completely integrate shared business processes into separate,

information on ERP systems.

B2B process invokes other functions that will incorporate processes like digital invoicing, inventorymanagement, electronic payment and auctioning finished products.

B2B exchanges are service hubs dedicated to a particular market, providing all the players in that market withthe opportunity to digitally communicate with each other.

Exchanges can deliver market specific information by providing access to industry directories, productdatabases, discussion forums, articles and industry specific bulletin boards. They can also act as a matchmaker

between multiple buyers and suppliers through the use of auctions and reverse auctions.

When there is the requisite amount of capability between the systems involved, the exchange can actuallyexecute transactions between members that wish to buy and sell, and its highest end, the exchange becomes a

market specific hub capable of dynamically integrating multiple supply chains and partners on demand.

INTRANET

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An Intranet is a network within an organization uses technology similar to internet that enables users to find,use, share documents and web pages.

Corporations use intranet to communicate with employees. In large companies, Intranet is being used by employees to obtain and share work-related documents, share

knowledge, transfer documents from one terminal to another, access e-learning tools and learn about company

news. Any message from company broadcast to all computers.

Intranets use traditional Internet protocols TCP/IP and HTTP to transfer data.

Advantages of Intranet:-

Intranet is based on Internet technologies and protocols. That means Intranet can make use of all thefacilities of Internet.

Intranet information is accessible using GUI based interface provided by web browsers. You can use thebrowsers such as Internet Explorer and Netscape Navigator.

Intranets are easier and less expensive to setup and maintain than traditional networks. Documents on Intranet are written in HTML. One can produce HTML documents using Microsoft Word by

saving the document as a web page. Since Intranets are based on Internet technology, they can also incorporate graphics, sound and video, e-

mail, newsgroups facilities.

Staff will find it simpler and more intuitive to use because it is accessed through a web browser provides aneasy, point and click interface.

An Intranet does not mean interconnection of a lot of people. Depending on your business need, it couldlink just 3 or 4 people in your organization.

DBA

DBA is a person or group of persons who is responsible for management of the database. DBA is a highly skilled person with strong technical background to monitor various operations such as creating, modifying and maintaining which help in handling three levels Of the database. DBA has most of the powers such as defining schemas, storage structures and access Method strategies, physical organization, authorization and integrity constraints etc. DBA are the top level authority among all the persons connected to the database.The main responsibilities of DBA are:

Deciding the information content of the database. Define the storage structure and access strategies. Defines external schemas for the users. Defines integrity constraints specifications. Granting of authorization for data access. Define strategy for backup and recovery. Installing and upgrading the DBMS and the application tools. Monitoring and optimizing the performance of the database. Plans the future storage requirements for the database system.

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SPAM

Spam is flooding the Internet with many copies of the same message, in an attempt to force the message onpeople who would not otherwise choose to receive it.

Most spam is commercial advertising, often for dubious products, get-rich-quick schemes, or quasi-legalservices.

There are two main types of spam and they have different effects on Internet users:-

Cancellable Usenet spam: - It is a single message sent to 20 or more Usenet newsgroups. Usenet spam is aimedat "lurkers", people who read newsgroups but rarely or never post and give their address away. Usenet spam

robs users of the utility of the newsgroups by overwhelming them with a barrage of advertising or other

irrelevant posts. Furthermore, Usenet spam subverts the ability of system administrators and owners to manage

the topics they accept on their systems.

Email spam:- It targets individual users with direct mail messages. Email spam lists are often created byscanning Usenet postings, stealing Internet mailing lists, or searching the Web for addresses. Email spams

typically cost users money out-of-pocket to receive.

POP3

Stands for Post Office Protocol". POP3, sometimes referred to as just "POP," is a simple, standardized method of

delivering email messages. A POP3 mail server receives e-mails and filters them into the appropriate user folders.

When a user connects to the mail server to retrieve his mail, the messages are downloaded from mail server to the

user's hard disk.

When you configure your e-mail client, such as Outlook (Windows) or Mail (Mac OS X), you will need to enter the

type of mail server your e-mail account uses. This will typically be either a POP3 or IMAP server. IMAP mail

servers are a bit more complex than POP3 servers and allow e-mail messages to be read and stored on the server.

Many "webmail" interfaces use IMAP mail servers so that users can manage all their mail online.

Still, most mail servers use the POP3 mail protocol because it is simple and well-supported. You may have to check

with your ISP or whoever manages your mail account to find out what settings to use for configuring your mail

program. If your e-mail account is on a POP3 mail server, you will need to enter the correct POP3 server address in

your e-mail program settings. Typically, this is something like "mail.servername.com" or "pop.servername.com." Of

course, to successfully retrieve your mail, you will have to enter a valid username and password too.

LINKER

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Linker is system software that combines or links the various object modules in order to create the executable form of

the program. The two main functions of a linker are to resolve a external references and to perform relocation. The

need of linker arises when source program consist of large number of modules, each of which may have been

separately compiled or assembled. In such a case compiler is able to compile each module of a program by itself

with little or no information from other parts of the program. Thus, it is responsibility of a linker to combine all such

object files produced by compiler and produce the executable form of the program. During the process of combining

object files, produced by compiler and produce the executable form of the program. During the process of

combining of object modules, the linker relocates them, since the codes are generated by assembler assuming the

same fixed start address for all the modules. Another responsibility of the linker is to resolve or adjust external

references. Linker also produces error messages if some external reference could not be resolved even after

consulting all the object modules

DEBBUGER

A debugger or debugging tool is a computer program that is used to test and debug other programs (the "target"program). The code to be examined might alternatively be running on an instruction set simulator(ISS), a technique

that allows great power in its ability to halt when specific conditions are encountered but which will typically be

somewhat slower than executing the code directly on the appropriate (or the same) processor. Some debuggers offer

two modes of operation - full or partial simulation, to limit this impact.

A "crash" happens when the program cannot normally continue because of a programming bug. For example, the

program might have tried to use an instruction not available on the current version of the CPU or attempted to access

unavailable or protected memory. When the program "crashes" or reaches a preset condition, the debugger typically

shows the position in the original code if it is a source-level debugger or symbolic debugger, commonly now seen

in integrated development environments. If it is a low-level debugger or a machine-language debugger it shows

the line in the disassembly (unless it also has online access to the original source code and can display the

appropriate section of code from the assembly or compilation).

THRASHING

If the number offrames allocated to a low priority process is lower than the minimum number required by the

computer architecture then in this case we must suspend the execution of this low priority process. After this we

should page out all of its remaining pages and freeing all of its allocated frames. This provision introduces a swap

in, swap-out level of intermediate CPU scheduling. Let take a example of a process that does not have enough

number offrames. If the process does not have the number offrames it needs to support pages in active use, itwill quickly page fault. The only option remains here for process is to replace some active pages with the page that

requires a frame. However, since all of its pages are in active use, It must replace a page that will be needed again

right away. Consequently, it quickly faults again and again that mean replacing pages that it must bring back in

immediately. This high paging activity is called Thrashing. Or we can say that a process is thrashing if it is

spending more time in paging then executing. Thrashing results in severe performance problems.

If the number of frames allocated to a low priority process is lower than the minimum number required by the

computer architecture then in this case we must suspend the execution of this low priority process. After this we

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should page out all of its remaining pages and freeing all of its allocated frames. This provision introduces a swap

in, swap-out level of intermediate CPU scheduling. Let take a example of a process that does not have enough

number of frames.

DYNAMIC WEBSITES

Dynamic websites contain Web pages that are generated in real-time .These pages include Web scripting code, such

as PHP or ASP, when a dynamic page is accessed, the code within the page is parsed on the Web server and the

resulting HTML is sent to the client's Web browser.

Most large websites are dynamic, since they are easier to maintain than static websites, this is because static pages

each contain unique content, meaning they must be manually opened, edited, and published whenever a change is

made. Dynamic pages, on the other hand, access information from a database .Therefore, to alter the content of a

dynamic page, the webmaster may only need to update a database record. This is especially helpful for large sites

that contain hundreds or thousands of pages. It also makes it possible for multiple users to update the content of awebsite without editing the layout of the pages.

Dynamic websites that access information from a database are also called database-driven websites.

MULTIPLEXER

In telecommunications and computer networks, multiplexing (also known as muxing) is a method by which multiple

analog message signals or digital data streams are combined into one signal over a shared medium. The aim is to

share an expensive resource. For example, in telecommunications, several telephone calls may be carried using one

wire. Multiplexing originated in telegraphy, and is now widely applied in communications.

The multiplexed signal is transmitted over a communication channel, which may be a physical transmission

medium. The multiplexing divides the capacity of the low-level communication channel into several higher-level

logical channels, one for each message signal or data stream to be transferred. A reverse process, known as

demultiplexing, can extract the original channels on the receiver side.

A device that performs the multiplexing is called a multiplexer (MUX), and a device that performs the reverse

process is called a demultiplexer (DEMUX)

STATIC WEBSITE

http://en.wikipedia.org/wiki/Telecommunicationshttp://en.wikipedia.org/wiki/Computer_networkshttp://en.wikipedia.org/wiki/Shared_mediumhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Multiplexing#Telegraphyhttp://en.wikipedia.org/wiki/Communication_channelhttp://en.wikipedia.org/wiki/Multiplexerhttp://en.wikipedia.org/wiki/Demultiplexerhttp://en.wikipedia.org/wiki/Demultiplexerhttp://en.wikipedia.org/wiki/Multiplexerhttp://en.wikipedia.org/wiki/Communication_channelhttp://en.wikipedia.org/wiki/Multiplexing#Telegraphyhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Shared_mediumhttp://en.wikipedia.org/wiki/Computer_networkshttp://en.wikipedia.org/wiki/Telecommunications

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A static website contains Web pages with fixed content. Each page is coded in HTML and displays the same

information to every visitor. Static sites are the most basic type of website and are the easiest to create. Unlike

dynamic websites they do not require any Web programming or database design. A static site can be built by simply

creating a few HTML pages and publishing them to a Web server.

Since static Web pages contain fixed code, the content of each page does not change unless it is manually updated

by the webmaster. This works well for small websites, but it can make large sites with hundreds or thousands of

pages difficult to maintain. Therefore, larger websites typically use dynamic pages, which can be updated by simply

modifying a database record. Static sites that contain a lot of pages are often designed using templates. This makes it

possible to update several pages at once, and also helps provide a consistent layout throughout the site.

APPLET

This Java program that can be embedded in a Web page. The difference between a standard Java application and a

Java applet is that an applet can't access system resources on the local computer. System files and serial devices

(modems, printers, scanners, etc.) cannot be called or used by the applet. This is for security reasons -- nobody

wants their system wiped out by a malicious applet on some wacko's Web site. Applets have helped make the Web

more dynamic and entertaining and have given a helpful boost to the Java programming language.

SDLC

In telecommunications and computer networks, multiplexing (also known as muxing) is a method by which multiple

analog message signals or digital data streams are combined into one signal over a shared medium. The aim is to

share an expensive resource. For example, in telecommunications, several telephone calls may be carried using one

wire. Multiplexing originated in telegraphy, and is now widely applied in communications.

The multiplexed signal is transmitted over a communication channel, which may be a physical transmission

medium. The multiplexing divides the capacity of the low-level communication channel into several higher-levellogical channels, one for each message signal or data stream to be transferred. A reverse process, known as

demultiplexing, can extract the original channels on the receiver side.

A device that performs the multiplexing is called a multiplexer (MUX), and a device that performs the reverse

process is called a demultiplexer (DEMUX)

http://en.wikipedia.org/wiki/Telecommunicationshttp://en.wikipedia.org/wiki/Computer_networkshttp://en.wikipedia.org/wiki/Shared_mediumhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Multiplexing#Telegraphyhttp://en.wikipedia.org/wiki/Communication_channelhttp://en.wikipedia.org/wiki/Multiplexerhttp://en.wikipedia.org/wiki/Demultiplexerhttp://en.wikipedia.org/wiki/Demultiplexerhttp://en.wikipedia.org/wiki/Multiplexerhttp://en.wikipedia.org/wiki/Communication_channelhttp://en.wikipedia.org/wiki/Multiplexing#Telegraphyhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Shared_mediumhttp://en.wikipedia.org/wiki/Computer_networkshttp://en.wikipedia.org/wiki/Telecommunications

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Model of System development life cycle

FLIP-FLOP

In digital circuits, a flip-flop is a term referring to an electronic circuit that has two stable states and thereby is

capable of serving as one bit of memory. A flip-flop is usually controlled by one or two control signals and/or a gate

or clock signal. The output often includes the complement as well as the normal output.

Uses:-

A single flip-flop can be used to store one bit, or binary digit, of data. Any one of the flip-flop type can be used to build any of the others. Many logic synthesis tools will not use any other type than D flip-flop and D latch. Level sensitive latches cause problems with Static Timing Analysis (STA) tools and Design for Test (DFT).

Therefore, their usage is often discouraged.

Many FPGA devices contain only edge-triggered D flip-flops

BINARY SEARCH TREE

First of all, binary search tree (BST) is a dynamic data structure, which means, that its size is only limited by amount

of free memory in the operating system and number of elements may vary during the program run. Main advantage

of binary search trees is rapid search, while addition is quite cheap. Let us see more formal definition of BST.

Binary search tree is a data structure, which meets the following requirements:

It is a binary tree; Each node contains a value; A total order is defined on these values (every two values can becomparedwith each other); Left subtree of a node contains only values lesser, than the node's value; Right subtree of a node contains only values greater, than the node's value.

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ARRAY

Array is a very basic data structure representing a group of similar elements, accessed by index. Array data structure

can be effectively stored inside the computer and provides fast access to the all its elements. Let us see an

advantages and drawbacks of the arrays.

Advantages

No overhead per element. Any element of an array can be accessed at O (1) time by its index.

Drawbacks

Array data structure is not completely dynamic. Many programming languages provides an opportunity toallocate arrays with arbitrary size (dynamically allocated array), but when this space is used up, a new array of

greater size must be allocated and old data is copied to it.

Insertion and deletion of an element in the array requires to shift O (n) elements on average, where n is size ofthe array.

CONSTRUCTOR

Aconstructor is a member function with the same name as its class. For example:

class X

{

public:

X(); // constructor for class X

};

Constructors are used to create, and can initialize, objects of their class type. You cannot declare a constructor as virtual or static, nor can you declare a constructor as const, volatile, or const

volatile.

You do not specify a return type for a constructor. A return statement in the body of a constructor cannot have areturn value.

MULTITHREADING

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Multitasking is performing two or more tasks at the same time. Nearly all operating systems are capable of

multitasking by using one of two multitasking techniques: process-based multitasking and thread-based

multitasking.

Process-based multitasking is running two programs concurrently. Programmers refer to a program as a process.

Therefore, you could say that process-based multitasking is program-based multitasking.

Thread-based multitasking is having a program perform two tasks at the same time. For example, a word processing

program can check the spelling of words in a document while you write the document. This is thread-based

multitasking.

OBJECT ORIENTED PROGRAMMING

This is popularly known as OOP and is a language centered on objects and following the four basic principles of

Abstraction, Encapsulation, Inheritance and Polymorphism.

Many programmers who have worked only in functional/ procedural languages such as C and Pascal often have

difficulty in understanding just what object oriented programming is. It is often referred to as a programmingparadigm based on objects and their interactions.

What is Object Oriented Programming?Examples

Since C++ and Java have procedural elements as well as an OOP element, a question often arises if they qualify as

per the definition object oriented programming language. The answer is Yes, although they are a mix and match of

procedural language + object orientation they pass all the parameters of OOP.

Many developers believe that using this definition object oriented programming is restricted to imperative

programming, which is not the case. PHP is a great example of a language that had a procedural origin but then

converted to object orientation to gain maximum benefits from OOP.

Objected Oriented Programming Classes & Objects

A good understanding of Classes and Objects is essential to understand just what object oriented programming is.

Classes and objects are used heavily to structure the program. The cruxes behind the definition object orientedprogramming is a collection of objects, which are instances of classes. Objects are accessible to the programmer via

an interface and they can send/ receive messages to other objects. The behavior of these objects is defined by its

methods.

ROUTERS

Routers are physical devices that join multiple wired or wireless networks together. Technically, a wired or wireless

router is a Layer 3 gateway, meaning that the wired/wireless router connects networks (as gateways do), and that the

router operates at the network layer of the OSI model.

Home networkers often use an Internet Protocol (IP) wired or wireless router, IP being the most common OSInetwork layer protocol. An IP router such as a DSL or cable modem broadband router joins the home's local

area network (LAN) to the wide-area network (WAN) of the Internet.

By maintaining configuration information in a piece of storage called the routing table, wired or wirelessrouters also have the ability to filter traffic, either incoming or outgoing, based on the IP addresses of senders

and receivers. Some routers allow the home networker to update the routing table from a Web browser

interface.

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INFRARED

Infrared frequencies are just below visible light. These high frequencies allow high speed data transmission. This

technology is similar to the use of a remote control for a TV. Infrared transmission can be affected by objectsobstructing sender or receiver. These transmissions fall into two categories.

(i)Point to point

(ii)Broadcast

(i) Point to Point: - Point to point infrared transmission signal directly between two systems. Many lap top system

use point to pint transmission. These systems require direct alignment between many devices.

Characteristics of Point to point:-

Wide range of cost Moderately easy installation. 100 k bps to 16 Mb of capacity. Variable attenuation. High immunity to EMI

(ii) Broad Cast: - These infrared transmissions use sprayed signal, one broad cast in all directions instead of direct

beam. This help to reduce the problems of proper alignment and abstraction. It also allows multiple receiver ofsignal

Characteristics of Broad Cast:-

In expensive. Single installation. 1M bps capacity.

SATELLITE MICROWAVES

The main problem with aero wave communication is the curvature of the earth, mountains & other structure often

block the line of side. Due to this reason, many repeats are required for long distance which increases the cost ofdata transmission between the two points. This problem is recommended by using satellites. Satellite micro wave

transmission is used to transmit signals throughout the world. These system use satellites in orbit about 50,000 Km

above the earth. Satellite dishes are used to send the signals to the Satellite where it is again send back down to the

receiver satellite. These transmissions also use directional parabolic antenna within line of side.

In satellite communication micro wave signals at 6 GHz is transmitted from a transmitter on the earth through the

satellite position in space. By the time signal reaches the satellites becomes weaker due to 50,000 Km distance. The

satellite amplifies week signals and transmits it back to the earth at the frequency less than 6 GHz.

Characteristics Satellite Micro waves:

High cost Extremely difficult and hare installation. Variable attenuation. Low immunity to EMI High security needed because a signal send to satellite is broadcasts through all receivers with in satellite.

COAXIAL CABLE

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Coaxial cable is very common & widely used commutation media. For example TV wire is usually coaxial.

Coaxial cable gets its name because it contains two conductors that are parallel to each other. The center conductor

in the cable is usually copper. The copper can be either a solid wire or stranded martial.

Outside this central Conductor is a non-conductive material. It is usually white, plastic material used to separate the

inner Conductor form the outer Conductor. The other Conductor is a fine mesh made from Copper. It is used to help

shield the cable form EMI.

Outside the copper mesh is the final protective cover. (as shown in Fig)

The actual data travels through the center conductor in the cable. EMI interference is caught by outer copper mesh.

There are different types of coaxial cable vary by gauge & impedance.

Gauge is the measure of the cable thickness. It is measured by the Radio grade measurement, or RG number. The

high the RG number, the thinner the central conductor core, the lower the number the thicker the core.

TRANSMISSION MEDIA

The means through which data is transformed from one place to another is called transmission or communication

media. There are two categories of transmission media used in computer communications.

BOUNDED/GUIDED MEDIA UNBOUNDED/UNGUIDED MEDIA

BOUNDED MEDIA:Bounded media are the physical links through which signals are confined to narrow path. These are also called guide

media. Bounded media are made up o a external conductor (Usually Copper) bounded by jacket material. Bounded

media are great for LABS because they offer high speed, good security and low cast. However, some time they

cannot be used due distance communication. Three common types of bounded media are used of the data

transmission. These are

Coaxial Cable Twisted Pairs Cable Fiber Optics Cable UNBOUNDED / UNGUIDED MEDIAUnbounded / Unguided media or wireless media doesn't use any physical connectors between the two devices

communicating. Usually the transmission is send through the atmosphere but sometime it can be just across the rule.

Wireless media is used when a physical obstruction or distance blocks are used with normal cable media. The three

types of wireless media are:

RADIO WAVES MICRO WAVES INFRARED WAVES

ENCAPSULATION

Encapsulation is the process of combining data and functions into a single unit called class. Using the method of

encapsulation, the programmer cannot directly access the data. Data is only accessible through the functions present

inside the class. Data encapsulation led to the important concept of data hiding. Data hiding is the implementation

details of a class that are hidden from the user. The concept of restricted access led programmers to write specialized

functions or methods for performing the operations on hidden members of the class. Attention must be paid to

ensure that the class is designed properly.

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Neither too much access nor too much control must be placed on the operations in order to make the class user

friendly. Hiding the implementation details and providing restrictive access leads to the concept of abstract data

type. Encapsulation leads to the concept of data hiding, but the concept of encapsulation must not be restricted to

information hiding. Encapsulation clearly represents the ability to bundle related data and functionality within a

single, autonomous entity called a class.

ABSTRACTION

Abstraction is one of the most powerful and vital features provided by object-oriented C++ programming language.

Modularity is very important in any programming language; it provides flexibility to users for using the

programming language. This aspect is well achieved with high performance by the concept of abstraction in C++. In

object-oriented programming language the programmer can abstract both data and code when needed.

The concept of abstraction relates to the idea of hiding data that are not needed for presentation. The main idea

behind data abstraction is to give a clear separation between properties of data type and the associated

implementation details. This separation is achieved in order that the properties of the abstract data type are visible to

the user interface and the implementation details are hidden. Thus, abstraction forms the basic platform for the

creation of user-defined data types called objects. Data abstraction is the process of refining data to its essential

form. An Abstract Data Type is defined as a data type that is defined in terms of the operations that it supports and

not in terms of its structure or implementation.

INHERITANCE

Inheritance is the process by which new classes called derived classes are created from existing classes called

base classes. The derived classes have all the features of the base class and the programmer can choose to add newfeatures specific to the newly created derived class.

For example, a programmer can create a base class named fruit and define derived classes as mango, orange,

banana,etc. Each of these derived classes, (mango,orange,banana, etc.) has all the features of thebase class (fruit)

with additional attributes or features specific to these newly created derived classes. Mango would have its own

defined features, orange would have its own defined features, banana would have its own defined features, etc.

Inheritance helps the code to be reused in many situations. The base class is defined and once it is compiled, it need

not be reworked. Using the concept of inheritance, the programmer can create as many derived classes from the base

class as needed while adding specific features to each derived class as needed.

SOFTWARE

Computer instructions or data. Anything that can be stored electronically is software. The storage devices and

display devices are hardware.

The termssoftware andhardware are used as both nouns and adjectives. For example, you can say: "The problem

lies in the software," meaning that there is a problem with the program or data, not with the computer itself. You can

also say: "It's a software problem."

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The distinction between software and hardware is sometimes confusing because they are so integrally linked.

Clearly, when you purchase a program, you are buying software. But to buy the software, you need to buy the disk

(hardware) on which the software is recorded.

Types of Software

System softwareThis is the software which is actually running your computer. This software handles different request for use the

hardware, many housekeeping work, storage of data etc. A good example of such system software is the Windows

program which is running your computer. Linux and UNIX are the other common system software available for

running computers.

Application softwareThese types of software are developed to handle a specific task and are developed to cater for the specific

requirement of the user. This could be the Payroll system or the Accounting system of your company. The system is

developed keeping all the requirements of the user in mind. But, for small companies it would not be a good idea to

develop software applications specifically for your use. To keep the system running properly, you should have

skilled IT expertise available to you and you might have to spend lots time and money to run the system properly.

EXPERT SYSTEM

An expert system is kind of a computer program which adopts a knowledge base of person to remove

complications or to illustrate ambiguities where generally more than one human professional would want to be

examined. Expert systems are much conformed in the given type of complication, and are a conventional appliance

and/or subset of the artificial intelligence (AI). Sample types of procedures may be adopted to counterfeit the

consummation of the professionals; however, similar to many or every are:

1) The formation of a knowledge base that adopts little knowledge representation architecture to grab the knowledge

of the Subject Matter Expert (SME).

2) A operation of aggregate that information via SME and condensing it subsequently to the architecture, that is

known as knowledge engineering. 3) The time instant when the system is get developed, it will be allocated in the universe complicated circumstance

like the human Subject Matter Expert (SME), customarily as a help to human peasant or like a addendum to

few useful data system. Expert systems can have or it may be possible that it do not have knowledge gaining

ingredients.

GAME PLAYING

Ever since the beginning of AI, there has been a great fascination in pitting the human expert against the

computer. Game playing provided a high-visibility platform for this contest. It is important to note, however,that the performance of the human expert and the AI game-playing program reflect qualitatively different

processes .

Game Playing

Computers, Games, and The Real World (if link fails, click here for a local copy) - This Scientific Americanarticle by Matthew Ginsberg discusses the current work being done in game-playing AI, such as the now-

famous Deep Blue. While it may seem somewhat frivolous to spend all this effort on games, one should

remember that games present a controlled world in which a good player must learn to problem solve rapidly,

and intelligently.

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Machine learning in Game playing - This resource page, assembled by Jay Scott, contains a large amount oflinks to issues related to machine game playing.

Report on games, computers and artificial intelligence - An updated, and easy to understand summary of thestatus of game playing and AI.

OPERATOR OVERLOADING

In computer programming, operator overloading (less commonly known as operator ad-hoc polymorphism) is a

specific case of polymorphism in which some or all of operators like +, =, or == have different implementations

depending on the types of their arguments. Sometimes the over loadings are defined by the language; sometimes the

programmer can implement support for new types.

Operator overloading is claimed to be useful because it allows the developer to program using notation "closer to the

target domain" and allows user-defined types a similar level of syntactic support as types built into the language.

DOMAIN

A domain contains a group of computers that can be accessed and administered with a common set of rules. For

example, a company may require all local computers to be networked within the same domain so that each computer

can be seen from other computers within the domain or located from a central server. Setting up a domain may also

block outside traffic from accessing computers within the network, which adds an extra level of security.

While domains can be setup using a variety of networking software, including applications from Novell and Oracle,

Windows users are most likely familiar with Windows Network Domains This networking option is built into

Windows and allows users to create or join a domain. The domain may or may not be password-protected. Onceconnected to the domain, a user may view other computers within the domain and can browse the shared files and

folders available on the connected systems.

Windows XP users can browse Windows Network Domains by selecting the "My Network Places" option on the left

side of an open window. You can create a new domain by using the Network Setup Wizard. Mac users using Mac

OS X 10.2 or later can also connect to a Windows Network by clicking the "Network" icon on the left side of an

open window. This will allow you to browse local Macintosh and Windows networks using the SMB protocol.

RELATIONAL KEYS

The word "key" is much used and abused in the context of relational database design. In pre-relational databases

(hierarchical, networked) and file systems (ISAM, VSAM, et al) "key" often referred to the specific structure and

components of a linked list, chain of pointers, or other physical locator outside of the data. It is thus natural, but

unfortunate, that today people often associate "key" with a RDBMS "index". We will explain what a key is and how

it differs from an index.

There are only three types of relational keys

Candidate Key

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As stated above, a candidate key is any set of one or more columns whose combined values are unique among

all occurrences (i.e., tuples or rows). Since a null value is not guaranteed to be unique, no component of a

candidate key is allowed to be null.

There can be any number of candidate keys in a table Relational pundits are not in agreement whether zero

candidate keys is acceptable, since that would contradict the (debatable) requirement that there must be a

primary key.

Primary KeyThe primary key of any table is any candidate key of that table which the database designer arbitrarily

designates as "primary". The primary key may be selected for convenience, comprehension, performance, or

any other reasons. It is entirely proper (albeit often inconvenient) to change the selection of primary key to

another candidate key.

Alternate KeyThe alternate keys of any table are simply those candidate keys which are not currently selected as the

primary key. According to {Date95} "... exactly one of those candidate keys [is] chosen as the primary key

[and] the remainder, if any, are then called alternate keys." An alternate key is a function of all candidate keys

minus the primary key.

ENTITY RELATIONSHIP DIAGRAM

An entity-relationship (ER) diagram is a specialized graphic that illustrates the relationships between entities in a

database. ER diagrams often use symbols to represent three different types of information. Boxes are commonly

used to represent entities. Diamonds are normally used to represent relationships and ovals are used to represent

attributes.

Also Known As: ER Diagram, E-R Diagram, entity-relationship model

Examples:Consider the example of a database that contains information on the residents of a city. The ER diagram shown in

the image above contains two entities -- people and cities. There is a single "Lives In" relationship. In our example,

due to space constraints, there is only one attribute associated with each entity. People have names and cities have

populations. In a real-world example, each one of these would likely have many different attributes.

DEADLOCK

In computer science, Coffman deadlock refers to a specific condition when two or more processes are each waiting

for each other to release a resource, or more than two processes are waiting for resources in a circular chain).

Deadlock is a common problem in multiprocessing where many processes share a specific type of mutually

exclusive resource known as a software lock or soft lock. Computers intended for the time-sharing and/or real-time

markets are often equipped with a hardware lock (or hard lock) which guarantees exclusive access to processes,

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forcing serialized access. Deadlocks are particularly troubling because there is no general solution to avoid (soft)

deadlocks.

This situation may be likened to two people who are drawing diagrams, with only one pencil and one ruler between

them. If one person takes the pencil and the other takes the ruler, a deadlock occurs when the person with the pencil

needs the ruler and the person with the ruler needs the pencil to finish his work with the ruler. Neither request can be

satisfied, so a deadlock occurs.

The telecommunications description of deadlock is weaker than Coffman deadlock because processes can wait for

messages instead of resources. Deadlock can be the result of corrupted messages or signals rather than merely

waiting for resources. For example, a dataflow element that has been directed to receive input on the wrong link will

never proceed even though that link is not involved in a Coffman cycle.

DATABASE REPLICATION

Database replication can be used on many database management systems, usually with a master/slave relationship

between the original and the copies. The master logs the updates, which then ripple through to the slaves. The slave

outputs a message stating that it has received the update successfully, thus allowing the sending (and potentially re-

sending until successfully applied) of subsequent updates. Multi-master replication, where updates can be submitted

to any database node, and then ripple through to other servers, is often desired, but introduces substantially increased

costs and complexity which may make it impractical in some situations. The most common challenge that exists in

multi-master replication is transactional conflict prevention or resolution. Most synchronous or eager replication

solutions do conflict prevention, while asynchronous solutions have to do conflict resolution. For instance, if a

record is changed on two nodes simultaneously, an eager replication system would detect the conflict before

confirming the commit and abort one of the transactions. A lazy replication system would allow both transactions to

commit and run a conflict resolution during resynchronization. The resolution of such a conflict may be based on a

timestamp of the transaction, on the hierarchy of the origin nodes or on much more complex logic, which decides

consistently on all nodes.

Database replication becomes difficult when it scales up. Usually, the scale up goes with two dimensions, horizontal

and vertical: horizontal scale up has more data replicas, vertical scale up has data replicas located further away in

distance. Problems raised by horizontal scale up can be alleviated by a multi-layer multi-view access protocol.

Vertical scale up is running into less trouble since internet reliability and performance are improving.

OPERATING SYSTEM

An operating system (OS) is a set of programs that manage computer hardware resources and provide common

services for application software. The operating system is the most important type ofsystem software in a computer

system. A user cannot run an application program on the computer without an operating system, unless the

application program is self booting.

Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting for

cost allocation of processor time, mass storage, printing, and other resources.

For hardware functions such as input and output and memory allocation, the operating system acts as an

intermediary between application programs and the computer hardware,[1][2]

although the application code is usually

executed directly by the hardware and will frequently call the OS or be interrupted by it. Operating systems are

found on almost any device that contains a computerfrom cellular phones and video game consoles to

supercomputers and web servers.

http://en.wikipedia.org/wiki/Computer_programhttp://en.wikipedia.org/wiki/Computer_hardwarehttp://en.wikipedia.org/wiki/Application_softwarehttp://en.wikipedia.org/wiki/System_softwarehttp://en.wikipedia.org/wiki/Dynamic_memory_allocationhttp://en.wikipedia.org/wiki/Operating_system#cite_note-0http://en.wikipedia.org/wiki/Operating_system#cite_note-0http://en.wikipedia.org/wiki/Operating_system#cite_note-0http://en.wikipedia.org/wiki/Cellular_phonehttp://en.wikipedia.org/wiki/Video_game_consolehttp://en.wikipedia.org/wiki/Supercomputershttp://en.wikipedia.org/wiki/Web_servershttp://en.wikipedia.org/wiki/Web_servershttp://en.wikipedia.org/wiki/Supercomputershttp://en.wikipedia.org/wiki/Video_game_consolehttp://en.wikipedia.org/wiki/Cellular_phonehttp://en.wikipedia.org/wiki/Operating_system#cite_note-0http://en.wikipedia.org/wiki/Operating_system#cite_note-0http://en.wikipedia.org/wiki/Dynamic_memory_allocationhttp://en.wikipedia.org/wiki/System_softwarehttp://en.wikipedia.org/wiki/Application_softwarehttp://en.wikipedia.org/wiki/Computer_hardwarehttp://en.wikipedia.org/wiki/Computer_program

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NORMALIZATION:

In the design of a relational database management system (RDBMS), the process of organizing data to minimize

redundancy is called normalization. The goal of database normalization is to decompose relations with anomalies in

order to produce smaller, well-structured relations. Normalization usually involves dividing large tables into smaller(and less redundant) tables and defining relationships between them. The objective is to isolate data so that

additions, deletions, and modifications of a field can be made in just one table and then propagated through the rest

of the database via the defined relationships.

SOFTWARE TESTING

Software testing is any activity aimed at evaluating an attribute or capability of a program or system and

determining that it meets its required results. Although crucial to software quality and widely deployed by

programmers and testers, software testing still remains an art, due to limited understanding of the principles of

software. The difficulty in software testing stems from the complexity of software: we cannot completely test a

program with moderate complexity. Testing is more than just debugging. The purpose of testing can be quality

assurance, verification and validation, or reliability estimation. Testing can be used as a generic metric as well.

Correctness testing and reliability testing are two major areas of testing. Software testing is a trade-off between

budget, time and quality.

Software Testing Types:

Black box testing Internal system design is not considered in this type of testing. Tests are based onrequirements and functionality.

White box testingThis testing is based on knowledge of the internal logic of an applications code. Alsoknown as Glass box Testing. Internal software and code working should be known for this type of testing.

Tests are based on coverage of code statements, branches, paths, conditions.

Unit testingTesting of individual software components or modules. Typically done by the programmer andnot by testers, as it requires detailed knowledge of the internal program design and code. May require

developing test drive modules or test harnesses.

BIOS

BIO (basic input/output system) is the program a personal computer's microprocessor uses to get the computersystem started after you turn it on.

It also manages data flow between the computer's operating system and attached devices such as the hard disk,video adapter, keyboard, mouse, and printer. BIOS is an integral part of your computer and come with it when

you bring it home. (In contrast, the operating system can either be preinstalled by the manufacturer or vendor or

installed by the user.)

BIOS is a program that is made accessible to the microprocessor on an erasable programmable read-onlymemory (EPROM) chip. When computer is turned on, the microprocessor passes control to the BIOS program,

which is always located at the same place on EPROM.

When BIOS boots up (starts up) your computer, it first determines whether all of the attachments are in placeand operational and then it loads the operating system (or key parts of it) into your computer's random access

memory (RAM) from your hard disk or diskette drive. With BIOS, your operating system and its applications

are freed from having to understand exact details (such as hardware addresses) about the attached input/output

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devices. When device details change, only the BIOS program needs to be changed. Sometimes this change can

be made during your system setup. In any case, neither your operating system nor any applicat