History of computers

History of computer can be goes back to the beginning of human culture. People used simple objects like stones and pebbles for counting.

The Evolution of Computers:

The history of computers spans thousands of years, from early counting devices to the powerful systems we use today. 

• The Abacus is known as the first device used for calculation around 600 BC. The modern form of the abacus appeared in the 16th century.
• Napier's Bones was a manually-operated calculating device invented by John Napier(1550-1617) to simplify multiplication and division.
• The first mechanical adding machine was invented by Blaise Pascal in 1642 (called Pascaline).
• In 1671,Baron Gottfried Wilhelm Leibniz invented the first calculator capable of performing arithmetic operations.
• Charles Babbage, a 19th century professor of Cambridge university, is considered to be "Father of modern digital computer".

1.   Babbage designed a difference engine in 1820 , which was used for calculation and printing of simple math tables.
2.  In 1842 , Babbage design an analytical engine that was completely automatic. It was used for solving complex mathematical problems.

Some well-known early computer:

 Mark -1 :

• Also known as automatic sequence controlled calculator, this was the first fully automatic calculating machine designed by

      Howard Aiken.
 ENAIC(1943-1946) [Electronic numeric integrator and calculator]:

• It was the first electronic as well as digital computer designed by J.P Eckert and J. Mauchly.
• It was developed as a result of military need.
• It occupied a wall space of 20*40 square feet & used 18,000 Vacuum tubes.

 EDVAC (1946-1952)[Electronic discrete variable automatic calculator]:

• It Was designed on stored-program concept .It was developed by John Von Neumann.

EDSAC(1947-1949)[Electronic delay storage automatic calculator]:

• Almost simultaneously with EDVAC in the U.S., the British developed the EDSAC.
• This machine was developed by a group of scientists headed by professor Mourice Wilkes .

 UNIVAC -1(1951)[Universal automatic computer]:

• It was the first commercially available digital computer.

IBM 650/701[International Automatic computer]:

• A commercially available digital computer that could be used for business and scientific

      calculations.

• It was the first commercial computer that sold over thousands of computers.