metallica,they a rap group or heavy metal band?  
Heavy metal. they have great songs like Battery, Mastery of puppets, fuel
never heard of the songs  but they started on 1981
Really?! They are a mega band that has had many amazing hits. Great music that gets you thumping when you are working out
really!  37 music videos!they were busy 
I would say. Actually the lead singer of Megadeth was the original singer for Metallica. But after the first album they broke up
interesting don't they have weird names for band members slayer and anthrax? 
Yes that is true. Can't forget Slipknot with their new age metal/rap mix
yes I've heard of his name guys were t-shirts that says that . popular they got 6 albums? is that correct  
I believe so, I have seen Slipknot twice 2nd row seats. Never got pleasure to see Metallica here even though they played in Cardinals baseball stadium