How would you define a computer?

Computers are. . .

Electronic devices that receives (input), processes & stores data & produces a result (output).

What are 4 things necessary to use a computer?

HardwareMachine

Wires

Transistors

Circuits

Software

Instructions or programs for controlling the computer.

DataText

NumbersSound

ImagesVideo

People

What are some advantages of using a computer rather than previous ways of doing things?

SpeedReliabilityAccuracyStorage

Communication

True or False?

Computers have been around for more than 50 years.

True!Late 1940’s – Early

1950’s

UNIVAC & ENIAC were examples of the first computers which were huge, had less processing power than today’s pocket calculators, cost millions of dollars, and were mostly used by the military and government.

Mid 1950’s – Early 1970’sSomewhat smaller & more powerful, but still limited in what they could do. Remained expensive – only major companies could afford them.

History continued. . 1971 - Dr. Ted Hoff

developed the microprocessor. Visionaries like Steve Jobs & Steve Wozniak saw the future for microprocessors & their application to personal computers.

They built the first Apple computer in 1976.

1980 – Bill Gates worked with IBM & developed the operating system for the IBM PC, which was introduced in 1981and quickly became the PC of choice in business.

What does it mean to be computer literate?

Computer Literacy is . . .

The ability to use a computer and its software to accomplish practical tasks.

How are computers used today?

2 Categories of Computers. . .Special Purpose

Used mostly to control something else with tiny chips.

Ex: dishwasher, airport radar system

General PurposeUsed for many purposes.Divided into 6 categories based on physical size, function, cost & performance. See pg. 8 in textbook.

Electronic Communication

Devices that share information.

History:1969 – ARPANET was

established, a large wide-area network created by the U.S. Defense Advanced Research Project Agency, sent first message via telephone lines from a computer at UCLA to another computer at Stanford Research Institute.

2 basic types of Computer Software (programs):

Application Software – a set of programs that performs specific tasks for users. Word processing, spreadsheets, databases, etc.

System Software – a set of programs that controls the operations of the computer and its devices. Windows or Mac operating system

Electronic communication requires 4 components. . .

Sender: the computer that is sending the message

Receiver: the computer that is receiving the message

Channel: the media that carries or transports the message (telephone wire, coaxial cable, microwave signal, or fiber optic)

Protocol: rules that govern the transfer of data

Networks. . .A group of 2 or more computer

systems linked together via communication devices. Enables computers to share resources

(printers, data, information & programs). Can consist of 2 computers or millions. Can connect all 5 categories of computers.

Computers on a network are called nodes or clients.

Servers are computers that allocate resources on a network.

What is the world’s largest network?

The Internet. . .History: Evolved from ARPANET Following the first historic message

between 2 computers in 1969, ARPANET grew quickly into a global network consisting of hundreds of military & university sites.

In 1990, the Internet was born.

How is the Internet used today?

Surf the Internet and the World Wide Web.E-mailChat roomsInstant messagingMailing listsNewsgroupsOthers???

How will computers affect our future?

They will be more powerful. They will be less expensive. Almost every type of job will somehow

involve a computer. More people will work from home. Wireless and mobile devices will

become the norm. Ability to connect with other

computers. Computer literacy will become even

more important. Ways we can’t even imagine!!