**Evolution of Computer**

In today’s world computer plays a vital role in everyday life. Almost in every house we can find a computer. The computer has become a basic need to the human life.

The reason behind it is everyone wants their work to be completed faster and in a efficient manner. In short we can say that computer is an electronic device which

stores and process the data and carries out sequence of operations.

The evolution of computer has started long before.

**In 2500BC – The ABACUS:**

Abacus is the first known calculating machine used for counting and arithmetic operations. The purpose of Abacus is to perform Addition, Subtraction, Multiplication

and division. Abacus is also called as counting frame. It consists of beads sliding on wires.

**In 1614 AD Napier ’s bones:**

John Napier a Scottish Mathematician invented Napier’s Bones. It has set of bones consist of 9 rods for each digit 1 through 9 and digit 0 as constant rod.

It is made up of strips of wood, metal and heavy cardboards. The rod’s surface comprises 9 squares, and each square, except for the top one, comprises

two halves divided by a diagonal line. The first square of each rod holds a single digit, and the other squares hold this number’s double, triple, quadruple,

quintuple, and so on until the last square contains nine times the number in the top square.

**1633 AD – The Slide rule:**

William Oughtred invented this Slide Rule. It is embodied by the two sets of scales that are joined together with a marginal space between them.

The main use of slide is for multiplication and division and also for roots, logarithm and trigonometry. Slide rule appear in a linear or circular form with a

standardized set of markings (scales) essential to perform mathematical operations.

**1642 AD – The Rotating Wheel Calculator:**

Rotating Wheel Calculator was invented by a French philosopher, blaise pascal. It is called as Arithmetic Machine, Pascal’s Calculator and later Pascaline,

it can add and subtract directly and multiply and divide by repetition.

**1842 AD – The Difference Engine:**

Difference Engine was developed by Charles Babbage, British Mathematicians and Engineers. A difference engine is an automatic calculator used to perform

polynomial functions. Both logarithmic and trigonometric functions, can be approximated by polynomials, so a difference engine can compute many useful sets

of numbers.

**1890 Hollerith Tabulating Machine:**

Hollerith Tabulating Machine was developed by the by Herman Hollerith and It was designed by using punched cards. He used punched card for storing and

processing information. Tabulating machine reads one card at a time, print portions of the card on fan folder paper and add one or more numbers punched on

the card to one or more counters, called accumulators.

**GENERATION OF COMPUTERS**

**FIRST GENERATION (1940-1956):**

In this first generation computer used Vacuum tubes for circuitry and Magnetic drums to store memory. In this type of computer only one problem can be solved

at a time. These computers are very large in size as it takes entire room. This type of computers can handle only one problem at a time. First generation computers

in this generation can understand only machine language, the lowest-level programming language to perform operations.

The vaccum tube was invented by an electrical engineer Lee De Forest in the year 1906. It was used in televisions, radios, radar and x-ray machines. The first computer

was named ENIAC (Electronic Numerical Integrator and Computer) was built with 18,000 vaccum tubes in the year 1943 funded by the university of Pennsylvania’s

Moore School of Engineering, and chief designers were J.Presper Eckert, Jr. And John W.Mauchly.

The length of the first computer is 30.5 meters long and twenty 10-digit registers for temporary calculations. Input was based on punch cards and paper tape.

Output came out on printouts. The Colossus was second machine during second world war . In this machine 1500 vaccum tubes are used to built.

UNIVAC and ENIAC are first generation computer examples. UNIVAC is the first commercial computer delivered for a business purpose by the U.S. Census Bureau in 1951.

**SECOND GENERATION (1956-1963):**

In the Second Generation of Computer, transistors came into use, the vacuum tubes were replaced by transistors. The replacement of transistor allowed computers

to become smaller, faster, cheaper, more energy-efficient.Second-generation computers moved from binary machine language to assembly, languages, which allowed

programmers to specify instructions in words. In this generation Punched cards were used for Input and Print-out for output. Transistors transfers the electric signals

across resistor. Magnetic core memory was used as primary memory and magnetic drum and magnetic tapes are secondary memory.

**THIRD GENERATION (1964-1971):**

Transistors were replaced with an integrated circuit known popularly as chips.In this generation integrated circuits has been developed were we can find transistors

in smaller size and these transistors are placed on a silicon chips. called semiconductors, which increased the speed and efficiency of computers.

Instead of punched cards and printouts, users are introduced with keyboards and monitors and interfaced with an operating system, which allowed the device to run

many different applications at one time with a central program that monitored the memory.The first Integrated Circuit was developed by Jack S Kilby at Texas

and by Robert S Noyce at Fairchild independently of each other. In this generation the digital equipment corporation was introduced first minicomputer for

commercially.

**FOURTH GENERATION (1971 – PRESENT):**

In this generation we could find thousand of integrated circuits were built into a single chip. This has reduced the size of the computer as compared to the earlier.

The Intel 4004 chip, developed in 1971, located all the components of the computer—from the central processing unit and memory to input/output controls—on a single chip.

**FIFTH GENERATION (PRESENT – BEYOND):**

This Generation will come close to bridging the gap between thinking and computing and it is completed as artificial intelligence. Because of this advance technology

we can make movies, 3D computer animation, make music, play video games.

The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.

So in today’s world, technology has made impossible things possible.