What Does PS/2 Connector (PS/2) Mean?
A Personal System/2 (PS/2) connector is a 6-pin connector used to connect peripheral devices, usually a mouse or keyboard, with a computer. Its name comes from the IBM series of personal computers, known as the Personal System/2. The PS/2 connector is the replacement of an older standard, DE 9 RS.232, used for mouse and keyboard connections.
Normally PS/2 connectors are available in two different sizes or shapes. One is 1/4 of an inch in diameter and other is 3/8 of an inch. Both sizes are on the market, but the smaller one is more commonly used. USB connectors have almost entirely replaced PS/2 connectors as the primary means of hooking up computer devices.
Techopedia Explains PS/2 Connector (PS/2)
In the early years of personal computing, PS/2 connectors were the easiest and best technology to connect a mouse and keyboard to a computer. Unfortunately, PS/2 ports can only connect two devices at same time if a splitter is used. By the early 2000s, PS/2 was considered a legacy port and USB was used to connect most peripherals. However, some motherboards still have built-in PS/2 ports and some computers give the option of connecting a mouse or keyboard through a USB port or a PS/2 port.
PS/2 originally had very few weak points regarding software and hardware. Software problems began cropping up in 2010 because most drivers quit supporting PS/2 connectors. This issue cannot be solved with the use of an adapter.
In addition to software issues, PS/2 doesn't support hot plugging. Because they weren't designed for frequent use, the ports and cables aren't very durable. The pins and the cable itself can be easily damaged, making fault isolation difficult. These disadvantages have sped the adoption of USB ports over PS/2 ports.