A computer chassis houses the main electronic components of the computer, including the motherboard, power supply, cooling system, and optional adapters, such as adapters that provide audio or video or networking capabilities. Typically, room is also provided for data storage, such as a hard disk or CD-ROM drive.
The chassis fulfills several functions. In addition to simply housing and protecting the electrical and mechanical components, it provides a mounting structure to which the components are secured in accordance with a design that efficiently interconnects them. It also provides a barrier for electromagnetic interference (EMI) caused by electromagnetic fields generated inside or outside the chassis.
Computer chassis designs often incorporate hooks, tabs, channels, screws, or the like for mounting circuit boards inside the chassis. These mounting methods often result in a reduction of useful surface area of the circuit board.