Expansion card

An expansion card in computing is a printed circuit board that can be
inserted into the expansion slot of a computer motherboard to add additional
functionality.

One edge of the expansion card holds the contacts that fit exactly into the
slot. The establish the electrical contact between the electronics (mostly
integrated circuits) on the card and on the motherboard.

The earliest type of PC expansion card was built to the industry-standard
architecture (ISA) specification and had a metal bracket at one end. This
bracket was fastened to the PC case with a screw. Connectors mounted on the
bracket allowed the connection external devices to the card. ISA cards are
now obsolete and have been replaced by PCI cards.

A PC graphics card (video card, VGA card) is a type of expansion card. It
usually sits in an AGP slot on the motherboard (there are cards for other
slot types, however), and has a VGA connector to the outside. The VDU or
monitor cable is attached to this connector.