Iron Maiden is a British heavy metal band formed in 1975 in London, England. The band was originally formed by bassist Steve Harris and guitarist Dave Murray, who remain core members today. The band gained popularity in the late 1970s and early 1980s with albums like Iron Maiden, Killers, and The Number of the Beast. They are known for their mascot Eddie, who appears on many album covers and in live shows. The band has had lineup changes over the years but continues to tour and release new albums, having sold over 100 million albums worldwide.