Those are the six realms and they are:
1.God Realm (Deva)
2.Asura Realm (The Jelous God)
3.Human Realm
4.Animal Realm
5.Preta Realm (The Hungry Ghost)
6.Hell Realm (Naraka)
I got most of the info from wikipedia and a manga called Reborn!
so this info is not my own.