A serial port on a PC is a male 9-pin connector (DE-9 D-sub). Early PCs had two 9-pin connectors or one 9-pin and one 25-pin (DB-25). On a PC, serial ports are called "COM ports," identified as ...

Maybe you needed a PS/2 connector or a serial port, the Apple Desktop Bus, or a DIN connector; maybe a parallel port or SCSI or Firewire cable. If you’ve never heard of those things, and if you ...