DEFINATION OF COMPUTER

Computer is an advanced/ modern electronic man made device, chich manipulates the data given as input then processes these data as per given instruction then gives output and store it for the future use too.
It is also a problem-solving machince, which can proccesses both numerical and non-numerical information.It is a totally user dependent device. it doesn't have its own brain,so it cannot think it's own.
In one word, any electronic machine that can perform'IPO'cycle is known as computer.
                                                                         This means it can execute a programmed list of
instructions and respond to new instructions that it is given. Today,the term is most often used to
refer to the desktop and laptop computers that most people use.
When referring to a desktop model, the term "computer" technically only refers to the computer itself -- not the monitor, keyboard, and mouse. Still, it is acceptable to refer to everything together as the computer.
If you want to be really technical, the box that holds the computer is called the "system unit."
Some of the major parts of a personal computer (or PC) include the motherboard, CPU, memory (or RAM),
Some of the major parts of a personal computer (or PC) include the motherboard, CPU, memory (or RAM), hard drive, and video card.
While personal computers are by far the most common type of computers today, there are several other types of computers.
For example, a "minicomputer" is a powerful computer that can support many users at once.
A "mainframe" is a large, high-powered computer that can perform billions of calculations from multiple sources at one time.
 Finally, a "supercomputer" is a machine that can process billions of instructions a second and is used to calculate extremely complex calculations.