IMO
Nu "metal" is absolute stuff and should not fall under the category of Metal. Most Nu "Metal" bands have some of the stufftiest names too. Real metal has good names, not this bull stuff like "Avenged sevenfold" or "System of a down" Real names are like Anthrax and Slayer
Alternative metal is okay
Heavy Metal is where it is at
Metalcore is good too.
Ministry is Industrial Metal, but just listen anyways.
Megadeth is a mixed metal band. Some of their songs are death metal, others are thrash, some are power, others hardcore. But all of it is good.