A personal computer (PC) is comprised of hardware, an operating system and software. Each of those components is fairly complex, however this article provides a basic description of their function and how they work together.
The most fundamental elements of a PC's hardware are the Central Processing Unit (CPU) and memory modules mounted onto a motherboard. When the PC is powered on, the CPU begins communicating with the motherboard and starts the Basic Input Output System (BIOS) which is stored on a chip on the motherboard. After verifying that the required components are present and functioning, it searches for an Operating System (OS). It may check the floppy drive, hard disk, CD-ROM or network for the presence of an OS.
Other common examples of hardware which may be a part of a PC include a modem, sound card, network card, and video card. The components attached outside of your computer such as the keyboard, mouse, printer and monitor are called peripherals.
For more information about each of the hardware components of a PC, see our article "The Parts of a Personal Computer". For more technical information about how the hardware works, refer to our articles for specific Hardware Info.