Not so off topic, playing on my own?

[Cribanox]

I've been playing on this server off and on for a year, and one time this guy started his own server during some of the DDOS attacks a while back, just to kill time.

Is it possible to start my own server just to kill time or when I'm bored, where I can go /godmode and just run around willy nilly? Don't really care to let others play, so I'm assuming I host the server on my pc somehow? Im not familiar with this kind of stuff.