A personal computer (PC) is a general-purpose computer, whose size, capabilities and original sale price makes it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator. This contrasted with the batch processing or time-sharing models which allowed larger, more expensive minicomputer and mainframe systems to be used by many people, usually at the same time. Large data processing systems require a full-time staff to operate efficiently.
Two main types:
Desktop model – the system unit sits horizontally on a desk and the monitor is placed on top.
Tower model – the system unit is vertical so can be placed on the floor to save desk space.