Key server (software licensing)

A key server is like a special computer that has a bunch of very important keys. Some computer programs, like games or design software, need these keys to work properly. When a person buys the program, they can get a key so that they can use the program. However, sometimes a company does not want a bunch of people using the same key, so they use a key server.

The key server is like a guard at the door. When a person tries to use the program, they have to knock on the door (or ask the key server) if they can come in. The key server checks if the person has a key, and if they do, the door opens (or the program works). If they don't have a key, the door stays locked (or the program doesn't work).

The key server also keeps track of who has a key and who doesn't. It makes sure that only one person uses a key at a time, so that there aren't too many people using the program. Think of it like a playground slide. Only one person can go down the slide at a time, and they have to wait their turn. The key server makes sure that people wait their turn to use the program, so that it works well for everyone.