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Introduction to Information Technology
Chapter 1
Mind Tools for Your Future
Chapter 1: Key Questions
1.1 How does information technology facilitate e-mail, networks, and the use of the Internet and the Web, and what is the meaning of the term cyberspace?
1.2 What are the five sizes of computers, and what are clients and servers?
1.3 What four basic operations do all computers follow, and what are some of the devices associated with each operation? How does communications affect these operations?
1.4 What are three directions of computer development and three directions of communications development?
What is Information Technology?
Information Technology(Infotech)– Merging computers with high speed communications links
Computer systems – Programmable, multiuser machines that accept data and
processes, or manipulate it into information we can use
Communications systems– electromagnetic devices and systems for communicating
over long distances
Infotech Examples
PCs Telephones Televisions Personal digital assistants
Communications – the Plumbing of Cyberspace
Cyberspace– Internet
Mother of all networks Over 400,000 smaller networks
– World Wide Web Part of the Internet Multimedia format
The Categories of Machines
Supercomputers Mainframe computers Workstations Microcomputers
– Desktop, tower, laptop, and PDAs
Microcontrollers– “Smart” appliances & automobiles
Servers & Clients
Server– Central computer– Holds databases and programs for clients
E.g., Web servers and mail servers
Clients– Linked by wired or wireless network– PCs, workstations, & other devices
How Computers Work?
Processes data into information – Data – raw facts and figures that are processed into information– Information – data that has been summarized or manipulated for
use in decision making
Uses hardware & software– Hardware – all machinery and equipment in a computer system– Software – instructions that tell a computer how to perform a task
Operates by performing:– Input – whatever is put in to a computer system– Processing – CPU processes data into information– Storage – store data/programs in memory and hard disks– Output – the results of processing– Communications - extends the power of the computer
The Basic Operations of a Computer
Input Hardware
Keyboard– Converts letters, numbers, and & characters into
electrical signals– Looks like a typewriter keyboard
Mouse - manipulates objects
Processing & Memory Hardware
Case Processor chip
– CPU- the brain
Memory chips– RAM
Motherboard– Main circuit board
Motherboard
Storage Hardware
Storage capacity – Byte – 1 character– Kilobyte – 1000 characters– Megabyte – 1 million characters– Gigabyte – 1 billion characters– Terabyte – 1 trillion characters
Storage Hardware
Hard disks– storage device that stores billions of
characters of data on a nonremovable disk platter
Floppy disks– stores data on removable 3.5-inch-diameter
diskette – Stores 1.44 million bytes
CD-ROM– storage device that stores billions of
characters of data on optical disks– Read only
Output Hardware
Devices that translate information processed by the computer into human readable forms
Peripheral devices – expands computer’s input, storage, and output capacities:
Video card Pair of speakers
Sound card Printer
Monitor
Communications Hardware
Modem– Sends and receives data over telephone lines– Mounted on an expansion card – Telephone line connects from a wall plug into the
back of the computer
Computer Software
System software– Performs essential operations– Enables application software to run
E.g., Windows 95/98/2000, Linux
Application software– Performs specific tasks– Requires system software
E.g., Word, Excel, Netscape,
Directions of Computer Development
Miniaturizations– Transistors– Integrated circuits
Speed– Faster
Affordability– Less expensive
Directions of Communications Development
Connectivity– Ability to connect computers by communications line
Interactivity– Two-way communication
Multimedia– Text, pictures, sound, & animation
Computers & Communications Combined
Convergence– computers, communications, consumer electronics,
entertainment,mass media Portability
– Portable and smaller Personalization
– Information tailored to personal preferences Information overload
Ethics & InforTech Concerns
Speed & scale– great amounts of information can be stored,
retrieved, and transmitted at a speed and on a scale not possible before
Unpredictability– a lot less predictable and reliable
Complexity– some computer systems are not even understood
by their creators