History of computer part -4 - Ts Read

Friday, 2 June 2017

History of computer part -4

Punched cards

Across the Atlantic. in USA, a big step forward was taken in the development of information processing. When the 1890 census was to be taken, the government was looking for a quick way of processing the census information. A man named Herman Hollerith came up with a new plan. He watched railway conductors punch passenger tickets and used the idea for the census. He suggested that all the census information be put on punched cards, with a special code devised for representing all numbers and letters. He then designed a machine to punch the census data onto the cards. To sort out and count the cards, after they had been punched, he designed a tabulating machine. Each card was put through a machine that had little rods that touched the card. Whenever there was a hole, a rod would go through the hole. This would allow electricity to flow through the rod. The number on that card could then be counted automatically. His inventions were a great success. The 1890 census results were ready in iust two and a half years. 

Hollerith went on then to found his own company to build these newly invented tabulating machines. His company eventually became part of IBM, one of the largest computer companies in the world. The first commercially available adding machine was introduced by William Burroughs 1892. It had two important innovations. Firstly, for inputting numbers, it used a typewriter style keyboard. Secondly, for recording numbers, it used a compact priming device.

It would be in place now to mention the contributions of two gentlemen: Shannon and Turing.

Shannon, Claude Shannon that is, constructed logic circuits that would eventually be used in modern computing. These were used to add, subtract, multiply and divide using Boolean Logic. Alan Turing was the man who first described how a machine could process any logical problem if it had an algorithm. So it was like this Shannon showed how a computer could be built and Turing showed how a computer could be applied.

Enter The Value

All these devices mentioned so far were mechanical. They were replaced shortly by the revolutionaries of the twentieth century: the valve and, later, the chip. With the arrival of these two, electronic computers with no moving parts. became a possibility.