For example, the analog VGA monitor interface uses a D-sub 15-pin plug and socket. Also called "DB connectors ... the letters A through E define the number of pins and follow the D.

D-subminiature ... of pins or sockets: A with 15, B with 25, C with 37, D with 50, and E with 9. This convention is often followed by a P (plug) or S (socket) - sometimes and M and F are used - to ...