History of Computers

Computer Technology Introduction

History of Computers

• A computer is a machine that works with data or information in the form of numbers.

• From the beginning of time and throughout the years, people have been inventing many things that would help them count.

COMPUTERS

• Why do we use computers?

• Who uses computers?

ABACUS

• first form of a computer

• a counting and calculating device

• simple but powerful• invented by the

Chinese• uses beads in columns• still in use today

ABACUS

ABACUS

• Look at the picture of an Abacus.

• Notice that the beads are in columns.

• When you add and subtract, you may also put your numbers in columns.

Punched Card

• Charles Babbage designed the Difference Engine

• Babbage also designed the Analytical Engine

• Both machines were to be powered by steam and punch cards to operate and turn gears

Charles Babbage

• tried to build a machine that would be able to do many of the things modern computers could do today

• he was never successful in completing his machines because the parts he needed to complete his work had yet to be invented

• he was a man before his time• he is well known as the “Father of Computers”

Charles Babbage

Charles Babbage

Even though Babbage could not make his computers work, he did establish the four functions of a computer that we use with all computers today.

Four Functions of the Computer

• Input• Processing • Output• Storage

InputExamples of input devices:

•Keyboard•Mouse•Scanner•Microphone•Digital Camera•Electronic Tablet•Digital Video Camera•PDA – Personal Digital Assistant

DATA

Data -- a collection of unorganized facts, which can include text, numbers, sounds

and images.

Data entered into a computer is called

INPUT.

PROCESSING

• The CPU -- Central Processing Unit is the “brain” of the computer.

• CPU processes the information or data.

OUTPUT

Examples of Output devices:

•Monitor•Printer•Speakers•Headphones

Output

• Output can be softcopy -- such as what appears on the monitor or what you hear through the headphones

• Output can be hardcopy (tangible) -- something you can touch.

STORAGEExamples of Storage devices:

•Diskette•Hard Drive•CD ROM•DVD•Flash Drive (Jump Drive)•Zip Drive•Tape Drive

DATA

The processed results are called OUTPUT.

Herman Hollerith

• invented the Tabulating Machine• was used successfully to speed up the work

involved in taking the government census• used punch cards to record and sort data or

information• began a company called the Computing-

Tabulating-Recording Company

Herman Hollerith

Hollerith’s company was later named

IBMInternational Business

Machines

ENIAC

• Electrical Numerical Integrator And Calculator

• first truly electronic-based computer

• used vacuum tubes• provided on/off switches• more than 18,000 switches• large system

John Mauchly with ENIAC

ENIAC

John Mauchly built the

ENIAC with J. Presper Eckert

Vacuum Tube

• used in the ENIAC

• was one of the most important technological developments in the history of computers

• looked like long light bulbs

Vacuum Tube

was an electronic device that controlled the flow

of electricity in the computer

TRANSISTORS

• Transistors -- in 1950’s transistors replaced the vacuum tubes to control the flow of electricity in computers. Transistors were considerably smaller in size and used less electricity.

INTEGRATED CIRCUIT

• Integrated Circuit or Chip -- In 1960’s the first integrated circuit was designed. It was the next great invention in the development of computers.

• This chip combines all the electronic parts a computer needs to run in one small place. It is about the size of your fingernail. A single chip contains circuits or pathways upon which electricity flows throughout the computer.

MICROPROCESSOR

• A microprocessor is an integrated circuit that not only contains electronic circuits but also memory storage for a computer.

• Microprocessors contain arithmetic, logic, and control units necessary for the operation of a computer. Aside from computers, microprocessors can also be found today in appliances and cameras.

For more information, click the link to visit http://www.computerhope.com/issues/ch000984.htm

This concludes our lesson on History of Computers