Such a difference between the melodic british rock and the stupid american equivalent... Iron Maiden, Judas Priest, Nazareth (ok, it's scottish ;0)), Queen, Slade...
The number of the beast! Just the best album they ever made. (although the next one was pretty good too. <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" />) Later on it became the album that made them popular.