Data ProcessingLesson 4

4-1 Early Developments in Electronic Data Processing

4- 2 Mark 14 - 3 The Eniac4 - 4 The Edvac4 – 5 Computer Generations4 – 6 First Generation Computers4 – 7 Second Generation Computers4 – 8 Third Generation Computers4 – 9 Fourth Generation Computer

Mark I

Howard Aiken began work on the Mark I at Harvard University

Mark I digital computer was completed in 1944

Mark I official name was Automatic Sequence Controlled Calculator.

Mark I functions: Could perform arithmetic operations Could locate information stored in

tabular form.

Mark I

Processed numbers up to 23 digits longs and could multiply three eight-digit numbers in 1 second.

It was not an electronic computer but as rather an electromechanical one

THE ENIAC

ENIAC – Electronic Numerical Integrator and Calculator

ENIAC was developed by Presper Eckert Jr. aand John Mauchly from 1943 to 1946.

It has 18,000 vacuum tubes and required the manual setting of switches.

It could perform 300 multiplications per second

The EDVAC

EDVAC is the modified version of ENIAC

EDVAC – Electronic Discrete variable automatic Computer

EDVAC employs binary arithmetic John von Neumann invented the

EDVAC

Computer Generations

1. First Generation Computers2. Second Generation Computers3. Third Generation Computers4. Fourth Generation Computers

First Generation Computers ( 1951-1959)

The use vacuum tubes in place of relays as a means of storing data in memory and the use of stored-program concept.

It requires 3.5 KW of electricity per day to keep the vacuum tubes running

Second Generation Computers ( 1959-1964)

Solid-state components ( transistors and diodes) and magnetic core storage formed the basis for the second generation of computers

Third Generation Computers ( 1965-1970)

Integrated solid-state circuitry, improved secondary storage devices and new input/output devices were the most important advances in this generation.

Fourth Generation Computers ( 1970 to present)

The major innovations were in the development of microelectronics and in the development of different areas in computer technology such as: multiprocessing, multiprogramming, miniaturization, time sharing , operating speed and virtual storage.

The Edvac