So In The old days of minecraft you could just run /gm 1 or /gm c. Then they changed it so it was only /gamemode 1 or /gamemode c.
However now on the latest versions you can only run /gamemode creative not even numbers work.
This plugin changes that. There are big plugins like essentials that does this but you don't always want to use essentials on your server.
You still require operator or the default Minecraft permission to change your gamemode. You can currently only change your own gamemode. But I may change that later.