About them Bans

How do the bans work, does it pop up with a notification, or what?
I started Gmod, nothing popped up, but I can't see any servers in the list..
Halp Pl0x!

You can still see the servers if you're banned I believe.
Try starting a single player game, it'll say if you're banned or not.

I'm banned from Gmod, you can still play single player if you are banned you can only not join/ create multi player servers.