Doneby

Pranav Krishna

Content:Calculating devices Electro-mechanical computersElectronic computers

Pre-Mechanical Computing:

From Counting on fingersto pebbles

to hash marks on wallsto hash marks on boneto hash marks in sand

Mechanical computers:The Abacus (c. 3000 BCE)

Napier’s Bones andLogarithms (1617)

Picture courtesy IBM

Pascaline (1645)Stepped Reckoner (1674) Jacquards loomDifference Engine Analytical Engine

Blaise Pascal’s

Pascaline (1645)

Gottfried Wilhelm von Leibnitz’sStepped Reckoner (1674)

Joseph-Marie Jacquard and his punched card controlled looms

(1804)

Preparing the cards with the pattern for the cloth

to be woven

Charles Babbage (1791-1871)The Father of Computers

Charles Babbage’s Difference Engine

Charles Babbage’s Analytical Engine

Electro-mechanical computers

FromHerman Hollerith’s

1890Census Counting Machine

to Howard Aiken

and the Harvard Mark I (1944)

Herman Hollerith and hisCensus Tabulating Machine

(1884)

A closer look at the Census Tabulating Machine

The Harvard Mark I (1944)aka IBM’s Automatic Sequence

Controlled Calculator (ASCC)

Electronic computers:Generation 1 ( the first digital computer)Generation 2 Generation 3Generation 4 Generation 5

Generation 1This is when the first digital computer was

builtIt was started to be built in 1937 and

finished in 1939 John Vincent Atanasoff, and Cliford Berry At Iowa State University This machine was not intended as general-

purpose computer, it was built to solve physics equations that Atanasoff was working on at the time

using electronic vacuum tubes, as the switching components

Generation 2This invention of the transistor which was

faster, smaller and required considerably less power to operate

This was introduced in 1959

Generation 3By the late 1960’s devices which included

more than one circuit on a single silicon chip became available

Generation 4In about 1970 the technology was available to

place an entire CPU on a single chip and the micro processor was born.