Metallica is one of my all time favorite bands. They are an American heavy metal band from L.A. 
I really like Metallica.  There was a album where Metallica played with a symphony.  It was my favorite.
They have been around since 1981 formed by Lars Ulrich.
That guy is the best!  Who are some of the other band mates?
Their current lineup includes James Hetfield, Lars Ulrich, Robert Trujillo, and Kirk Hammet.
Is metallica still touring?
I'm not sure but their fast tempos, aggressive musicianship and instrumentals made them one of the "big four" bands of thrash metal with Anthrax, Slayer, and Megadeth.
How many albums have they sold over the years?
I don't know exactly, but some former members of the band are Guitarist Dave Mustaine and bassists Cliff Burton, Jason Newsted, and Ron McGovney.
Have they had a lot of number 1 hits?