Often the primary input for computer games. It boasts a very large versatility for direct input.
Keyboards are versatile devices that lend themselves to many arrangements, especially when paired with other input devices like a mouse. It is a kind of input.
Keyboards have a ton of possible button inputs, but also their own interesting quirks in things such as holding multiple keys. If your question has to deal specifically with keyboard issues, as opposed to general input concerns that would affect both keyboard and gamepad users, this tag is an appropriate choice.