Prior to the advent of the microprocessor, a computer was usually built in a card-cage case or mainframe with components connected by a backplane
consisting of a set of slots themselves connected with wires; in very
old designs the wires were discrete connections between card connector
pins, but printed-circuit boards soon became the standard practice. The
central processing unit, memory and peripherals were housed on individual printed circuit boards which plugged into the backplane.
During the late 1980s and 1990s, it became economical to move an
increasing number of peripheral functions onto the motherboard (see below). In the late 1980s, motherboards began to include single ICs (called Super I/O
chips) capable of supporting a set of low-speed peripherals: keyboard,
mouse, floppy disk drive, serial ports, and parallel ports. As of the
late 1990s, many personal computer motherboards supported a full range
of audio, video, storage, and networking functions without the need for
any expansion cards at all; higher-end systems for 3D gaming and computer graphics typically retained only the graphics card as a separate component.
The early pioneers of motherboard manufacturing were Micronics,
Mylex, AMI, DTK, Hauppauge, Orchid Technology, Elitegroup, DFI, and a
number of Taiwan-based manufacturers.
Popular personal computers such as the Apple II and IBM PC had
published schematic diagrams and other documentation which permitted
rapid reverse-engineering and third-party replacement motherboards.
Usually intended for building new computers compatible with the
exemplars, many motherboards offered additional performance or other
features and were used to upgrade the manufacturer's original equipment.
The term mainboard is archaically applied to devices with a single
board and no additional expansions or capability. In modern terms this
would include embedded systems, and controlling boards in televisions,
washing machines etc. A motherboard specifically refers to a printed
circuit with the capability to add/extend its performance/capabilities
with the addition of "daughterboards".
