Here are some of the basics on some basic computer parts and their functions:
A motherboard is also called the main board or system board. The motherboard is the most complicated piece of equipment inside the computer case. The primary function of a motherboard is to provide a structure for all components and devices of a computer to interface with each other. A device that is not installed directly on the motherboard is called a peripheral device.
The central processing unit (CPU) is also called the processor or microprocessor. As its name implies, this device is central to processing done by the the computer. It is the brain of the computer. It is the component in which most processing takes place.
The processor uses temporary storage, called primary storage or memory to temporarily hold both data and instructions while it is processing them. Primary storage is much faster to access than permanent storage. Primary storage is volatile; it loses its contents when power is removed. Primary storage is provided by devices called memory or random access memory (RAM).
The most popular permanent storage or secondary storage devices are hard disk drives, solid state drives, USB flash drives, digital versatile discs (DVDs), compact discs (CD-ROMs) and or floppy disks.
Hard drives are presently (as of 2008) the most important permanent storage devices. A hard drive stores the information available to a computer when the computer is turned off (unlike RAM which loses all its contents once the computer is powered down).
A power supply unit (or PSU) is the component that supplies power to a computer. Most personal computers can be plugged into standard electrical outlets. The power supply then pulls the required amount of electricity and converts the AC (alternating current) to DC (direct current). Computers require DC to give power to components. The power supply also regulates the voltage to eliminate spikes and surges common in most electrical systems. Not all power supplies, however, do an adequate voltage-regulation job, so a computer can be susceptible to large voltage fluctuations.
Firmware – Software that is permanently stored on a chip. The basic input/output system (BIOS) on a motherboard is an example of firmware.
A basic input/output system (or BIOS) is the software that determines what a computer can do without accessing programs from a hard drive or other secondary storage devices. On personal computers, the BIOS contains all the code required to control the keyboard, display screen, disk drives, serial communications, and other miscellaneous functions. The BIOS makes sure all the hard drives, ports, operating system and central processing unit function together. The BIOS is typically placed in a computer chip on the motherboard (it is often called read-only memory basic input/output system or ROM BIOS). This ensures that the BIOS will always be available and will not be damaged by hard drive failures.
The following and more can be configured in the BIOS:
Hard disk drive parameters
Boot sequence
Shadow RAM
Date and Time
Floppy disk drive parameters