USB Alternative

PS/2

PS/2 is a legacy computer input interface used mainly for keyboards and mice.

Characteristics

PS/2 characteristics

Compare its connector, device role, USB overlap, and current status.

Primary purposeKeyboard and pointing-device input
Common connector6-pin Mini-DIN
General peripheral dataNo
Typical devicesKeyboards and mice
USB relationshipUSB HID devices largely replaced dedicated PS/2 keyboards and mice
Hot-plug focusNo; legacy PS/2 systems were not designed around USB-style hot plugging
Current statusLegacy and specialized

Sources: Linux Kernel Input Documentation, Linux Kernel PS/2 Protocol Support, and USB-IF HID and Device Class Specifications.