PS/2 ports were originally designed for use in IBM's second generation of personal computers in 1987, but they're still widely used today. PS/2 cables connect peripheral devices like mice and keyboards to computers. The cables feature a 6-pin connector, and they're often color-coded—green for mice and purple for keyboards—in order to aid users in making proper connections.
PS/2 Extension Cables and PS/2 Adapters
Although most mice and keyboards feature an attached cord, these cords may be too short, and newer computers and laptops do not always feature PS/2 ports in which to plug these cables. A number of extenders, adapters, and converters are available for purchase online and in computer stores.
Perhaps the most common adapter type is the PS/2 to USB adapter, which allows users to plug PS/2 devices into USB ports. These adapters often allow users to plug both a mouse and keyboard into a single USB port, saving space for other devices.