Multiplayer Server List - Symbol left to number players?

[Nocke]

I am wondering what that could mean: Entering the multiplayer menu, in the servers list, there is a sort of icon for some servers left to the number of actual players, looking a little like a key.

Could anybody plesase enlighten me?

 

Thx a lot!

[Matze81]

It's a joystick symbol, meaning that particular server is for joystick users only. People using mouse aim cannot play on such a server.