# Write short note on Origin of Computers.

## Origin of Computer:

The computers were invented to compute, and the basic role of computers was to calculate, or to perform lengthy calculations in seconds. In order to count large numbers various systems of numeration were generated, such as:

- Babylonian System of Numeration,
- Greek System of Numeration,
- Roman System of Numeration, and
- Indian System of Numeration (decimal system of numeration 0-9).

**But we should be proud to know that our Indian System of Numeration has been accepted universally.**

**Abacus:**

Since civilizations began, many of the advances made by science and technology have depended upon the ability to process large amounts of data and perform complex mathematical calculations. For thousands of years, mathematicians, scientists and businessmen have searched for computing machines that could perform calculations and analyze data quickly and efficiently. One such device was the abacus. The literal meaning of Abacus is the calculating board.

The Chinese hold the credit of inventing ‘abacus’. The abacus can be thought of a counting frame, with vertical wires, with seven beads on each wire. A horizontal divider separates the top two beads from the bottom five, sometimes referred to as the heaven and the earth beads. The user manipulates the beads by using the principle of positional weight of beads on a rack.

## **Napier’s Bone**.

**Napier’s Bone** is a device invented in 1617 A. D. by John Napier, a mathematician. He invented the logarithms to reduce any multiplication problem.

**Slide Rule:**

Slide rule, is a mechanical analog computer. It was developed by English mathematician E. Gunter. The slide rule is used primarily for multiplication and division, and also for functions such as roots, logarithms and trigonometry, but it is not normally used for addition or subtraction.

**Pascal’s Calculator:**

The credit of building calculator goes to Blaise Pascal, a French mathematician and scientist. The machine was also called Pascaline, it could add and subtract directly and multiply and divide by repetition.

**Leibniz’s Multiplication and Dividing Machine:**

German mathematician Gottfried Wilhelm Leibniz invented a digital calculator around 1672 which was called the step reckoner. It was the first calculator that could perform all four arithmetic operations: addition, subtraction, multiplication and division.

**Difference Engine:**

Charles Babbage, an English mathematics professor told that all the mathematical operations. even the most complexed ones, can be broken down into simple operations. This concept could be used to make it able to be carried out by a machine in loop. This machine used the decimal number system and was powered by cranking a handle. It could be called the first step towards the creation of computers. That is why he is called as the Father of the Computers.

**The Analytical Engine:**

Due to some reasons Babbage left working on Difference Engine and he started working on Analytical Engine which was even closer to the concept of today’s computers. Because it was a proposed mechanical general-purpose computer. It had an arithmetical unit, control flow in the form of conditional branching and loops, and an integrated memory.

**Mechanical and Electrical Calculator:**

Calculators are very popular device for arithmetic calculation, Calculators were developed in the 19th century. The mechanical calculator was developed first and later on the rotating part of mechanical calculator was replaced by electric motor. That kind of calculators were called electrical calculator.

**Modern Electronic Calculator:**

The electronic calculators were succeeded by modern electronic calculator. An electronic calculator is a small, portable. usually inexpensive electronic device used to perform the basic operations of arithmetic. It has a keypad representing digits and mathematical operations. Some calculators can also store some numbers temporarily and permanently.