What is computer?
Computer is an electronic machine. It has the capacity to act depending on the given instructions. The instruction may be like “add 2 and 3” or “subtract 2 from 3”. But the instructions should be in specified format specified by a computer language. Unlike calculator the computer can do not only arithmetic operations but also logical operation.
Computer works as per the given set of instructions what is known as program. It gets data as input and operates on it as per the instructions given in the program and produce the output. Obviously an input device is required to feed input data to the computer system, a memory to store programs and data, a processor to execute the program in order to process the data and an output device to show the result to the user.