A device that allows one system to connect to and work with another. An adapter may be a simple circuit that converts one set of signals to another; however, the term often refers to devices which are more accurately called "controllers." For example, display adapters (graphics cards) and network adapters (NICs) perform extensive processing. See host adapter
and expansion bus
Flash Memory Adapters
After the SD card debuted for cameras, mini and micro versions were introduced for cellphones. The smaller cards can be inserted into SD card adapters and accessed by readers with full-size slots. See SD card
New interfaces are constantly appearing, and adapters connect the old with the new.