A local PIN is a device-bound numeric login method used to unlock a session directly on the endpoint. Unlike a password that may be checked against a remote identity system, the PIN is validated on the device itself and is usually tied to that specific hardware and user profile.
In cyber security, local PINs matter because they change how access is controlled on shared or managed devices. They can improve usability and speed, but they also need strong policy support: short or simple PINs are easier to guess, and stolen devices are still at risk if physical protection is weak. Defenders often pair PIN use with enrollment controls, lockscreen limits, recovery requirements, and enforced reauthentication so the PIN remains one factor in a broader trust model.