Unit 1 : Computing Fundamentals Lesson Topic

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• Identifying Computers

• Desktop Computers

• Notebooks or Laptop Computers

• Tablets

• Hand-held or Mobile Computers

Lesson 1 : Computers all around Us

• System unit

• Microprocessor chip

• How memory is measured

• What ROM is

• What RAM is

• How memory works

Lesson 2 : Elements of a Personal Computer

• Storage systems

• Hard disk drives

• Optical drives

• Portable or removable storage devices

Lesson 3: Working with Storage Systems

• Hardware

• Input/output devices

• Input devices

• Output devices

• Using Software

• Software Copyright.

Lesson 4 :Using Input/output Devices

• A Computer is a general purpose device that can be programmed to carry out

a set of arithmetic or logical operations. It consists of at least one processing

element, typically a central processing unit (CPU) and some form of memory.

• Integrated in our work, home, and social environments

• Perform a multitude of tasks

• Computers can be:

− Designed specifically as computing devices

− Embedded in products

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Identifying Computers Computers all

around Us

• Called personal computers

• Sit on, beside, or under desk

• Process data quickly

• Typically used in small businesses, schools, and homes.

• Generally two types

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PC

Mac

Desktop Computers Computers all

around Us

• Advantages

− Portability

− Power consumption considered “greener” alternative

− Can purchase accessories to enhance enjoyment and experience

• Netbook

− Similar to notebook but smaller and less expensive

− Designed to handle wireless communications or access to

Internet only 4

PC Notebook

Mac Notebook

Notebooks or Laptop Computers Computers all

around Us

• Similar to notebook for portability and connection to data

• Screen can swivel or fold over

• Uses touch screen capability for data entry

− With finger, pen device, or built-in keyboard

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Tablets Computers all

around Us

• Often most important and expensive part

• Separate devices inside box perform specialized

functions

• Notebook has same components as desktop

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System Unit Elements of

a Personal Computer

• Microprocessor chip

− Often called “brain” of computer as instructions from

software programs and input received are executed

here

− Referred to as Central Processing Unit (CPU).

− Processes information and instructions at different speeds

− Hertz (Hz) measures speed of internal computer clock in terms of

frequency or number of cycles per second

− Dual and quad core processors contain two or four processor chips

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System Unit - Microprocessor chip

Elements of

a Personal Computer

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Processor (CPU) MHz or GHz

8088 (XT) 4 to 10 MHz

80286 (286 or AT) 8 to 16 MHz

80386SX/DX (386SX/DX) 16 to 33 MHz

80486 (486) 25 to 100 MHz

Pentium (MMX) 166 to 200 MHz

Pentium PRO 150 to 200 MHz

Pentium II 200 to 400 MHz

Pentium III 500 MHz to 1.2 GHz

Pentium 4 or Pentium M 1.4 to 3.2+ GHz

Pentium 5 5 GHz to 7 GHz

System Unit - Microprocessor chip

Elements of

a Personal Computer

• Computers developed using numbering system of 1s and 0s or binary system

• For computer to store information, must have memory chips installed

• All data made up of bytes in combinations calculated by computer

− Every file used in software program has specific file size

− Data file size increases or decreases based on contents stored

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Memory

Elements of

a Personal Computer

• Memory measured in bits and bytes

− Bit is smallest unit of data used by computers

− Group of eight bits make one byte

1 Kilobyte = 1,024 Bytes

1 Megabyte = 1,048,576 Bytes

1 Gigabyte = 1,073,741,824 Bytes

1 Terabyte = 1,099,511,627,776 Bytes

1 Petabyte (PB) = 1,125,899,906,842,624 Bytes

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Memory – Cont’d.

Elements of

a Personal Computer

• Group of integrated circuits responsible for:

− Starting computer

− Checking RAM

− Loading operating system

• Occurs only when computer first turned on or each time you restart (reboot)

computer

• Reads information entered and processes it during time it resides in memory

− When process complete, clears itself and waits for next entry

− Does not perform any tasks other than reads information and

processes it 11

Read Only Memory (ROM) BIOS Elements of

a Personal Computer

• Located in system unit as electronic memory pool where computer holds copies

of programs and data

• Temporarily stores software program currently using and data created in

program; may be referred to as system RAM

• RAM is volatile

• Measured in nano seconds (ns)

• Used in video display cards or to buffer information sent to printer

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Random Access Memory (RAM) Elements of

a Personal Computer

1. ROM BIOS takes control when computer started and loads operating system

2. When operating system gains control, see Windows “splash screen”

− Operating system checks Windows “registry,” which identifies what

hardware and software installed

− When complete, see Windows “desktop”

3. Certain amount of RAM used to run basic files

− As computer performs specific tasks, it uses RAM needed

− When starting software “application” or program, asking computer to put

copy of program in RAM

− Close application program when not in use to make RAM available 13

Understanding How Memory Works Elements of

a Personal Computer

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• RAM is temporary so you must save work to storage device

• Storage device you use depends on amount of storage you need and speed of

data retrieval or data transfer rate

• Hard disk drives used most often to store and retrieve software programs and

data

• Can use other media such as flash drive or optical disc for backup or

portability purposes

What are storage systems? Working with storage

systems

• Disk drive performs three functions:

− Rotates disk at constant speed to access sectors on entire disk surface

− Moves read/write head across tracks on entire disk surface

− Reads data from disk and writes data to disk using read/write head

• Data from RAM written on disk arranged in tracks divided in sectors

• Process of preparing disk for use is called formatting

− Places special information on each track that marks location of each sector

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Disk Drivers Working with storage

systems

• Primary storage area for both data and programs

− Software programs must be installed on hard drive

− Hard drive stores and retrieves information at high speeds

• Data transfer rate (throughput) of hard drive is function of hard drive rotation

speed and number of heads per surface

− The higher the rotation speed and/or number of heads,

the less time it takes to find data

− Range in capacity from 100 MB to 100+ GB

− Also used in network servers where drives very large to accommodate

requirements of whole organization and data storage requirements

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Hard Disk Drivers Working with storage

systems

• Designed to read flat, circular disc, commonly referred to as Compact Disc

(CD) or Digital Versatile/Video Disc (DVD)

− Read by laser device or optical drive that spins disc at speeds from

200 rpm or higher

• CD-ROM (Compact Disc Read Only Memory) or DVD-ROM drive

− Similar to player in audio/video entertainment system

− Information written or burned onto surface and retrieved with laser beam

− Can only read data

• New computers come with at least one optical drive

− Usually DVD optical drive or CD/DVD optical writer drive.

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Optical Drivers Working with storage

systems

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• Also known as burner drive, looks and acts like regular optical disc drive

− Software comes with optical writer drive to “burn” or write data onto a disc

• Formats of drives include:

− CD-R/ DVD-R: can write once only to blank disc, but disc can be read

multiple times

− CD-RW/ DVD-RW: can read and write multiple times onto same disc

− DVD-RAM: similar to DVD-RW but can only be used on devices that

support this format; usually in the form of cartridges

• Blank discs relatively inexpensive, with -R disks cheaper than -RW

• Size of disc can be 650 or 700 MB, while DVDs can be 4.7GB to 17+GB with

rapid access speeds

• Special software needed to manipulate or edit video before burned to DVD

Optical Writers Working with storage

systems

• Removable media systems can include flash memory cards, sticks or USB

flash key/thumb drives, or external hard drives

− Benefits include portability, large storage size, and data-sharing

capability

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Removable storage devices Working with storage

systems

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Hardware Using Input/output

devices

• The physical parts of a computer are collectively known as hardware.

• Internal hardware is located within the main box (system unit) of the computer.

• External hardware is located outside the system unit and plug into connectors called ports located on the exterior of the system unit.

• Enables communication between user and computer

• Three classifications of Input/output devices:

− Send information to computer

− Display or transmit information from computer

− Communicate between computers

• Input device

− Anything used to enter data into computer

• Output device

− Anything used to display data on or from computer

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Input/output Devices Using Input/output

devices

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Input/output Devices Using Input/output

devices

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Input Devices Using Input/output

devices

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Output Devices Using Input/output

devices

1. Monitor

2. Projector

3. Plotter

4. Speaker

5. Printer

(Dot

Matrix)

6. InkJet

7. Laser

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Software Using Input/output

devices

• The programs or instructions used to tell the computer hardware what to do.

• System software allows a computer to operate and run application software.

• Application software performs specific tasks or applications.

• Device driver

− Mini-program tells operating system what kind of device it is, what make or

brand it is, and its purpose

− Main purpose is to enable communication between operating system and device

• Plug-and-play

− Automatically identifies new device connected so it looks for and installs device

automatically

− If cannot find right driver, will need to use software that came with device or

search for driver on Internet

• Important to have correct driver for device to work properly

− If special features included with device, correct driver ensures features will be

available 26

Device Driver Using Input/output

devices

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Software Copyright Using Input/output

devices

• Software copyright is the extension of copyright law to machine-readable

software.

• Software copyright is used by proprietary software companies to prevent

the unauthorized copying of their software.

• free and open source licenses also rely on copyright law to enforce their

terms.

• A copyleft is a type of copyright license that allows redistributing the work

(with or without changes) on condition that recipients are also granted

these rights.

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Software Copyright

(Freeware & Shareware) Using Input/output

devices

• Freeware is copyrighted computer software which is made available for use

free of charge, for an unlimited time. Freeware refers to software that anyone

can download from the Internet and use for free.

• Shareware refers to commercial software that is copyrighted, but which may

be copied for others for the purpose of their trying it out with the

understanding that they will pay for it if they continue to use it. Sharewares

give users a chance to try the software before buying it.