A. The word computer is derived from Latin word Computare. The meaning of computare is calculate or programmable machine. The computer is an electronic machine to calculate, store, interpret the data. Simply we can term it is a human machine to finish our daily task easily. It requires electricity to perform like how man needs food and water. Computer has a special language like how people speak in their own language. To generate result from the computer, we need to give command.
B. The first mechanical computer is designed by Charles Babbage. It was invented for the analytical purpose and it occupied 1800 square feet of the room. It weighed around 50 tons and used 18,000 vacuum tubes. Now that we are lucky to have very small computers and smart devices which are portable to use and complete our task within seconds of time.
C. Computer device has three main parts. They are
1) Input devices: The devices are keyboard, mouse which are responsible for giving command to the computer.
2) CPU (Centre Processor Unit): This is an analysing unit.
3) Output devices: These are responsible to display output. Monitor, printer and speakers comes under output devices.