Topic 3. What is a computer?

A computer is a machine with an intricate network of elec­tronic circuits that operate switches or magnetize tiny metal cores. The switches., ike the cores, are capable of being in one or two possible states, that is, on or off; magnetized or demag­netized. The machine is capable of storing and manipulating numbers, letters and characters (symbols).

The basic idea of a computer is that we can make the ma­chine do what we want by inputting signals that turn certain switches on and turn others off, or magnetize or do not magne­tize the cores.

The basic job of computers is processing of information. For this reason computers can be defined as devices which accept information in the form of instructions, called a program, and characters, called data, perform mathematical and /or logical operations on the information, and then supply results of these operations. The program, or part of it, which tells the comput­ers what to do and the data, which provide the information needed to solve the problem, are kept inside the computer in a place called memory.