History of computer

Introduction:-  

The computer is an essential tool of present day in society. Today computer gives us the information we need to extend our thinking power, with invention of new technology equipments our way of living has modify a lot of steps. We use computer in every field of life example- Business, research, Communication, Entertainment, banking, etc.

 The word computer comes from Greek word “compute” “which means to calculate”.

Definition of computer:-

A computer is an electronics machine or devices that automatically accepts data and process it and gives the output result under the instruction.

v  An electronic machine, operating under the control of instructions stored in its own memory;

Ø  Accepts data (Input)

Ø  operate the data according to particular rules (Process)

Ø  Generate results (Output)

Ø  Saves the results (Storage) for forthcoming  future use

Advantage of computer?

Computers have been invented to help people. It provides lot of advantages over manual operation. Let us look at few of them:-

1.   Speed: -

A computer is a very fast device. It can perform in a few seconds the amount of work that a human can do in entire year. A powerful computer is capable of performing about 3 to 4 million arithmetic operations per second.  It performs maximum works in minimum time. Data stored in the files can also be retrieved at a very high speed.

2.   Accuracy: -

 The word “accuracy” means ‘exactness of result’. The computer never gives wrong information until the user deliver instruction to no match data to pc.

Reliability: - the computer performs reparative jobs without making any mistakes and without getting tired .computer does not fail and rarely need maintenance.

3.   Versatility: -

Computer can do a variety of jobs (instruction) depending on their hardware characteristic and according to instruction provide to them. It makes balance sheet, accounting chart, Electricity bills, telephone bills, railway reservation, Entertainment etc.

4.   Power of memory: -

 A computer can store and recall any amount of information because of its secondary storage device. It stores data, knowledge, results, for long time which is not possible for human mind because human brain forgets 90 % of storages.

5.   IQ (Intelligence quotient):-

A computer has no IQ “it means – it is not a magical device”. It performs a task that human being can do. But different is that it performs these tasks by unthinkable speed and accuracy. 

History of computer:-

Abacus: - 

 This was first mechanical device developed in 3500 BC. Abacus consisted of beads which could slide over writes. The wire represented columns the right most column represented units. It by moving appropriate beads are could do addition and subtraction and represented various numbers.

Pascal‘s Adding machine: --

A popular mechanical calculator, capable of performing addition, and subtraction,, was developed by the great French philosopher and scientist Blaise Pascal in 1642.  Mechanical device included blaise PASCAL’s adding machine (1642) which was operated by dialling wheels and dials. When one wheel moved through a complete revolution the adjacent wheel moved through 1/10 of revolution. It was able to perform addition and subtraction automatically.

Charles Babbage analytical engine (1833):-- 

In 1823, Charles Babbage, English mathematicians, designed a mechanical computing machine for automatic computation of mathematical tables. He called this machine ‘DIFFERENCE ENGINE” this only arithmetic operation to be performed was addition.   Charles Babbage, considered as the ‘father of the modern computer’ had the detailed design for the ‘ANALYTICAL ENGINE’.

This machine was designed to perform any mathematical calculation automatically. In this machine all essential components of a modern digital computer such as processor capable addition, subtraction, multiplication, division. It memory units decimal counting wheels.

It contained the following components.

1. An arithmetic unit which was called ‘mill’ where calculations were performed. It was capable to performing addition, subtraction, multiplication, and division.
2. A memory to store data and intermediate results. It consisted of decimal counting wheels. It capacity was of one thousand 50-digit decimal numbers.
3. A mechanism consisting of gears and shafts to transfer data and results between store (memory) and mill(ALU) in order to control the sequence of operations Babbage to use punched cards.
4. Input and output devices. Babbage proposed to supply numerical information either by punched cards or by manually setting counter wheels. It was intended to get the output data either printed on paper or punched on cards.

 Babbage was the first man to give the concept of a programmable machine having components similar to a modern computer and hence he is called father of computers.