Iron Maiden was one of the pioneers of heavy metal and has been a major contributor to the genre. The rockers never relied on media attention, which may be a part of the reason that the band has endured for more than 20 years and retained their popularity through change after change in mainstream musical preference.

Formed in 1976, the British foursome gained popularity among London rockers in the late '70s before releasing their first record, the self-titled Iron Maiden, in 1980. Though it's sometimes considered a bit of a rush job, the album sold well in the U.K. regardless, thanks to the song "Running Free." The band took a harder approach on their follow-up effort, Killers, in 1981, which was shortly followed by the departure of two band members, including vocalist Paul D'Ainno.

It was when the famed Bruce Dickinson joined the fray that Iron Maiden became the band that dominated the metal scene. The band's third album, Number of the Beast, is considered by some to be one of the greatest rock records of all time. The album's title track and the single "Hallowed Be Thy Name" were smash hits. The group released Piece of Mind and Powerslave, the tour for which would provide cuts for 1985's Live After Death, which included live versions of the band's most popular titles.

After another album and more touring, 1988's Seventh Son of a Seventh Son became Iron Maiden's most heralded effort since Number of the Beast. After yet another tour, guitarist Adrian Smith left the group and the band went on hiatus. With Janick Gers on board, Maiden released No Prayer for the Dying in 1990, a record that seemed to draw on the band's roots more than their most recent work. The single "Bring Your Daughter...to the Slaughter" gave the band their first number one hit in their native U.K. After expressing their desire to pursue other projects, Dickinson stayed on for one more album, Fear of the Dark, which debuted at number one on the U.K. charts and became one of the best most successful efforts.

After a few live albums, the band introduced Dickinson's replacement, Blaze Bayley, to the world on The X Factor. Apparently the true X factor had been Dickinson as the album failed to achieve the success of many of the groups previous records. After subsequent efforts received little praise, Bayley was ousted and Dickinson returned in 1999 for a tour and a new album, Brave New World. Maiden has continued to release a series of live albums DVDs as well as new material as in their most recent effort, 2006's Matter of Life and Death.