In which year when computer was invented?

Answer 1

Charles Babbage in 1822 devised the Difference Engine that was capable of complex mathematics and in 1833 devised the Analytical Engine that was capable of complex logic. Alan Turing discovered the concept of a Turing Complete machine ie a machine with the ability to perform any sort of computational logic task. The Analytical machine was the first such that could be defined as Turing Complete. The first general purpose digital (ie built with vacuum tubes rather than valves or switches) computer produced was the Colossus in 1944 developed by the British Defence. It was enormous, nowhere near desktop size. Given it was built for a specific purpose and to be extraordinarily good at that purpose, the Colossus can also be defined as the world's first supercomputer. With the development of the solid state transistor in 1947 and the subsequent development of the integrated circuit in 1958 the microchip was developed, integrating many thousands of transistors in one compact package. This meant computers could now be built the size of desktops. The first desktop computer was the IBM System/360 in 1964 but was a mainframe. The Altair 8800 was developed in 1975 for hobbyists mainly. Finally in 1976 Steve Jobs and Steve Wozniak developed the first personal desktop computer, the Apple 1. It was pre-built and allowed the use of a monitor and a keyboard.