__HISTORICAL EVOLUTION OF COMPUTER__

__HISTORICAL EVOLUTION OF COMPUTER__

**The ascent of computer is very old.It took long duration to mature.Ancient people used stone,bones,beads etc for calculation and to keep record but as a civilization developed, people felt the need for calculating devices.The earliest and the simplest device that was used for calculation was the Abacus.**

**THE ABACUS**

**Abacus was the first calculating device which is developed in china in 500 BC.Later it spread all over the world many countries like Japan,Russia, and other countries developed their own Abacus.**

**It was a manual device it consist of a wooden frame which was divided into two portions vertically.These two portions were divided by mid-bar.The smaller part is known as Heaven and the other part is known as earth.The beads in Heaven which are closed to mid-bar denote the digit zero.In digit one and the ones in lower part represents zero.**

**The beads are move according to set roles in order to solve problems of calculations.The Abacus was capable of adding and subtracting only.**

**NAPIER’S BONES**

**Napier’s bones was invented by SIr John Napiera great mathematician of Scotland in 1617 AD.It was also a manual device.This device was made up of boxes and rodes.It consists eleven sticks with members carved on them.These sticks are called bones as they were made of bones.Napier’s bone was capable in solving addition, subtraction, multiplication,division.**

**THE PASCALINE**

**Pascaline was also a calculating device.It was invented by a French mathematician, Blaise pascal in 1442 AD.It worked on the principle of clock mechanism.This machine consisted of chain and toothed wheels.The teeth on each wheel represented numbers from 0 to 9. Each wheel from right to left represents units,tens,hundreds,thousands and so on. This machine was capable to do addition and subtraction with accuracy and a high speed.**

**LEIBNITZ CALCULATOR**

**Leibnitz Calculator was invented by a German mathematician,Golttfried Leibnitz in 1671. It was an improvement over pascaline. Leibnitz’s machine was also called ‘Stepped Calculator’.It was able to solve addition, subtraction , multiplication, and division.**

**JACQUARDS’S LOOM**

**Joseph jacquard, a textile manufacturer, invented this machine called jacquard’s Cards in 1801.He used punched cards to produce complex cloth patterns automatically.Its entire operation was under a program’s control and its weaving process was automatic with the invention of punched cards, the important information can store and retrieve easily.**

**DIFFERENCE ENGINE**

**Charles Babbage, a British mathematician,know as “Father of modern computer” developed this machine in 1822.Difference Engine was capable to calculate various mathematical operations and mathematical tables.**

**ANALYTICAL ENGINE**

**After the success of difference engine, Charles Babagge developed another device called Analytical Engine in 1833.Analytical Engine worked on concept used in Automated loom and Difference Engine.He included the concept of control processor,storage area and input-output devices in his machine.It had almost all parts of a modern computer.This machine was capable of doing addition, subtraction, multiplication, division as well as logical operations.**