What does it mean if the server says its.white listed

Question

This one server says "the server is whitelisted"and I dont know what that means

Answer 1

That means that the server you're trying to connect to is using what's known as a whitelist. A whitelist is a list of usernames that are allowed to connect to the server. If your name is not on this list, you won't be able to join the server.

If you want to be put on the whitelist, try contacting a sever op or moderator.

(Most larger public servers require you to follow the steps on their website to be put on the whitelist.)