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