An AutoDJ fills in any gaps in your schedule or you can just let it run to without having to schedule anything.
An AutoDJ runs on the Stream Host Providers platform. The way it works is that you load it up with songs, Station IDs, commercials, jingles, etc and turn it on. It runs itself. It is your radio station automated in hands-off mode. So, your station is on air 24/7 until you interrupt it and decide to do a live broadcast from home.
You cannot “DJ” on an AutoDJ. That is, speak on a microphone. You do what is called “LiveDJ” when you broadcast from your computer using SAM Broadcaster Pro.
So, you want both a way to do “live” streams from your home studio and you will want an AutoDJ to run when you are not personally broadcasting.