The first motherboard (mainboard) design apperead in 1982, on the original IBM PC. It was a large printed circuit board, taht contained the 8080 microprocessor, the BIOS, sockets for the CPU's RAM and a collection of slots for auxiliary cards.

If you wanted to add a floppy drive or parallel port or a joystick, you bought a separate card and plugged it into one of the extension slots.

The motherboard, by enabling pluggable components, allows users to personalize a computer system depending on their applications and needs.

The motherboard is, in many ways, the most important component in your computer (not the processor, even though the processor gets much more attention.) If the processor is the brain of the computer, then the motherboard and its major components (the chipset, BIOS, cache, etc.) are the major systems that this brain uses to control the rest of the computer. Having a good understanding of how the motherboard and its contained subsystems works is probably the most critical part of getting a good understanding of how PCs work in general.

• The motherboard plays an important role in the following important aspects of your computer system:
• Organization: In one way or another, everything is eventually connected to the motherboard. The way that the motherboard is designed and laid out dictates how the entire computer is going to be organized.
• Control: The motherboard contains the chipset and BIOS program, which between them control most of the data flow within the computer.
• Communication: Almost all communication between the PC and its peripherals, other PCs, and you, the user, goes through the motherboard.
• Processor Support: The motherboard dictates directly your choice of processor for use in the system.
• Peripheral Support: The motherboard determines, in large part, what types of peripherals you can use in your PC. For example, the type of video card your system will use (ISA, VLB, PCI) is dependent on what system buses your motherboard uses.
• Performance: The motherboard is a major determining factor in your system's performance, for two main reasons. First and foremost, the motherboard determines what types of processors, memory, system buses, and hard disk interface speed your system can have, and these components dictate directly your system's performance. Second, the quality of the motherboard circuitry and chipset themselves have an impact on performance.
• Upgradability: The capabilities of your motherboard dictate to what extent you will be able to upgrade your machine.