Chapter 1
Computers in Your Life




Computers are prevalent in the home, in the school, in the workplace, and on the go.
Most professional jobs and skilled trades heavily depend on the creation, collection, evaluation and
dissemination of information.
Uses of computers include word processing, e-mail exchange, shopping, research, investments
management, playing games and many other applications.
Knowledge of computers assists the consumer to purchase the right computer, save money on repairs
and use the computer to maximum benefit.
What Is a Computer and What Does It Do?
A computer is a programmable electronic device that accepts data and performs operations on that
data.
 Input—entering data into the computer.
 Processing—performing operations on the data.
 Output—presenting the results.
 Storage—saving data, programs, or output for future use.
Computers Then and Now



The computer as we know it is a fairly recent invention.
The history of computers is often referred to as generations, from pre-computers and early
computers (before 1945) to fifth generation computers (now and the future).
Each new generation is characterized by a major technological development.
Hardware








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.
An input device is used to input data into the computer.
A processing device performs calculations and comparisons necessary for processing. The main
processing device is the central processing unit (CPU).
An output device presents the results to the user.
Storage devices are used to save data, programs or output.
Communication devices allow the user to communicate with others and access remote information.
Software



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.
Data and Information


Data = raw, unorganized facts.
 Can be in the form of text, graphics, audio, or video.
Information = data that has been processed into a useful form.
Computer Users and Professionals


Computer users, or end users, are the people who use a computer to obtain information.
Programmers are computer professionals whose job it is to write the programs that
computers use.
Computer Networks and the Internet




A computer network links computers together so that users can share hardware, software, and
data, as well as electronically communicate with each other.
Network servers manage resources on a network.
Clients are computers on the network that access resources via the network server.
Computer networks are commonly found in businesses, schools, and homes.
The Internet



The Internet is the largest and most well-known computer network in the world.
Individuals connect to the Internet using an Internet service provider (ISP).
E-mail and accessing Web pages are two of the most common Internet activities.
Accessing a Network




Need a modem or network adapter to connect to the network.
Software (often built into the operating system) allows you to log on to the network and access
resources.
Need an ISP and Web browser to access Internet resources.
Many networks and Internet connections require a user ID and password to log on to the network.
Computers to Fit Every Need

Five basic categories





Mobile devices
Personal computers
Midrange servers
Mainframe computers
Supercomputers
Mobile Devices



Very small computing devices.
Usually based on a wireless phone or pager.
Many can be used to access e-mail and Web pages.
Personal Computers







Microprocessors allow for the creation of computers small enough to fit on a desk or lap.
PC compatible—based on the original IBM PC; typically run the Windows operating system.
Macintosh—a type of personal computer manufactured by Apple.
Desktop computers—small enough to fit on or next to a desk. Can use:
 Desktop case
 Tower case
 All-in-one case
Portable PCs—designed to be carried around.
 Notebook computers
 Tablet PCs (either slate or convertible)
 Handheld computers (pocket computers)
PCs designed for just network use are referred to as network computers (NCs) or thin
clients.
Devices designed just for Internet access are called Internet appliances.
Midrange Servers


Medium-sized computers, also called minicomputers or midrange computers.
Fall between microcomputers and mainframes in processing power.
Mainframe Computers



Standard choice for most large organizations.
Specialize in high-volume processing of business transactions.
Also called high-end servers or enterprise-class servers.
Supercomputers



Used for applications that have extraordinary demands for processing power.
Offer very fast speeds and extreme degrees of accuracy.
Commonly created today by connecting hundreds of smaller computers to form a supercomputing
cluster.
Computers and Society



The information age = the prominence of information technology.
There are many benefits of a computer-oriented society, including making many tasks in our
lives go much faster.
Risks include health, security, ethical, and privacy concerns.
Key Terms
application software
audio
computer
data
desktop-case
hard disk drive
hardware
information
kiosk
Macintosh
memory
microcomputer
midrange server
monitor
mouse
peripheral device
software
supercomputer
punch cards
vacuum tubes
transistors
ICs
ports
system unit
network adapter
Linux
Visual Basic
client
ISP
network
processing
programmer
system software
the Internet
user