Consider the sockets on a Mother Board. There are internal sockets, and external sockets.
Discuss the design aspects (shape, number of pins, serial, parallel, and form factor); define each of these; discuss SATA, ATA, VGA, USB, and the others in the Wikipedia article. Why has SATA persisted since the inception? Why did the Mini-DIN connector disappear? Is there a general principle that predicts the longevity of connectors.