The motherboard has been an integral part of most personal computers for more than 20 years. Think of a motherboard as a scale model of a futuristic city with many modular plug-in buildings, each using power from a common electrical system. Multiple-lane highways of various widths transport data between the buildings. The motherboard is the data and power infrastructure for the entire computer.

Motherboards (also called mainboards) are actually a carryover from architecture used for years in mainframe computers. Various circuit cards performing various functions all plug into many similar sockets on a common circuit board. Each circuit card performs a unique function in the computer and gets its power from the socket.

Due to improvements in circuitry and packaging, motherboards have essentially stayed the same size or shrunk while their functionality has skyrocketed. In this edition of HowStuffWorks, you will learn how the motherboard operates and what its many sockets and connectors do.