An electronic lock (or electric lock) is a locking device that operates by means of an electric current. Electric locks are sometimes stand-alone
with an electronic control assembly mounted directly to the lock. More often electric locks are connected to an access control system. The advantages of an electric lock connected to an access control system include key control, where keys can be added and removed without re-keying the lock cylinder; fine access control, where time and place are factors; and transaction logging, where the activity is recorded.
Electric locks use magnets, solenoids, or motors to actuate the lock by either supplying or removing power. Operating the lock can be as simple as using a switch, for example, an apartment intercom door release, or as complex as a biometric-based access control system. There are two basic types of locks: “preventing mechanism” or operating mechanism.