The Beatles are one of the most influential and popular rock 'n' roll bands of all time. The foursome from Liverpool, England, consisted of the legendary songwriting team of John Lennon and Paul McCartney and also included lead guitarist George Harrison and drummer Ringo Starr.

After waiting at least a decade, Beatles fans will be able to purchase sonically upgraded reissued albums in stereo and mono. Apple Corps and EMI will release individual CDs and two boxed sets, one in stereo and one in mono, on September 9, 2009.

The Beatles first formed in Liverpool in 1957 under the name "The Quarrymen." After replacing their original drummer Pete Best with Ringo Starr, the Beatles secured their first record contract with the help of manager Brian Epstein. Their debut album, Please Please Me, was released in 1963 and helped bring them to the attention of UK critics and music fans.

"Beatlemania" hit the States in 1964 after the band appeared on The Ed Sullivan Show, creating an unprecedented demand for merchandise and films that featured "the Fab Four." On top of infectious early No. 1 hits like "She Loves You" and "I Want to Hold Your Hand," the musicians' long hair and wise-cracking antics inspired a fan frenzy never before seen in popular music.

Assisted by producer George Martin, the Beatles' sound matured dramatically as the Sixties wore on, with albums like Sgt. Pepper's Lonely Hearts Club Band revolutionizing the way pop music was written and recorded. The band disbanded in 1970, only eight years after making its first recording. They had 27 No. 1 hits in all in America and Britain, all of which were included on the 2000 release The Beatles 1, which reached the top of the charts in over 35 countries and was the 15th best-selling album internationally as of 2007.

John Lennon was shot and killed by a crazed fan outside his New York City apartment in 1980, and Harrison died of lung cancer in 2001. McCartney continues to release well-received solo albums and is a huge draw in concert, while Starr released Liverpool 8 in early 2008.