The Beatles were the most popular and influential rock act of all time, but their significance cannot solely be measured in sales records (as impressive as those are). They synthesized all that was good about early rock and roll, and changed it into something original and even more exciting. They established the prototype for the self-contained rock group that wrote and performed their own material. As composers, their craft and melodic inventiveness were second to none, and key to the evolution of rock from its blues/R&B-based forms into a style that was far more eclectic, but equally visceral. As singers, both John Lennon and Paul McCartney were among the best and most expressive vocalists in rock; the group's harmonies were intricate and exhilarating. As performers, they were (at least until touring had ground them down) exciting and photogenic; when they retreated into the studio, they were instrumental in pioneering advanced techniques and multi-layered arrangements. They were also the first British rock group to achieve worldwide prominence, launching a British Invasion that made rock truly an international phenomenon.

Guitarist and teenage rebel John Lennon got hooked on rock 'n' roll in the mid-1950s, and formed a band, the Quarrymen, at his Liverpool high school. Around mid-1957, the Quarrymen were joined by another guitarist, Paul McCartney, nearly two years Lennon's junior. A bit later they were joined by another guitarist, George Harrison, a friend of McCartney's. The Quarrymen would change lineups constantly in the late 1950s, eventually reducing to the core trio of guitarists.

The Quarrymen changed their name to the Silver Beatles in 1960, quickly dropping the "Silver" to become just the Beatles. Lennon's art college friend Stuart Sutcliffe joined on bass, but finding a permanent drummer was a vexing problem until Pete Best joined in the summer of 1960. He successfully auditioned for the combo just before they left for a several-month stint in Hamburg, Germany. When they returned to Liverpool at the end of 1960, the band--formerly also-rans on the exploding Liverpudlian "beat" scene--were suddenly the most exciting act on the local circuit. They consolidated their following in 1961 with constant gigging in the Merseyside area, most often at the legendary Cavern Club.

They also returned for engagements in Hamburg during 1961, although Sutcliffe dropped out of the band that year to concentrate on his art school studies there. McCartney took over on bass, Harrison settled in as lead guitarist, and Lennon had rhythm guitar; everyone sang. In mid-1961 the Beatles (minus Sutcliffe) made their first recordings in Germany, as a backup group to a British rock guitarist-singer based in Hamburg, Tony Sheridan. (Sutcliffe, tragically, would die of a brain hemorrhage in April 1962).

Near the end of 1961, the Beatles' exploding local popularity caught the attention of local record store manager Brian Epstein, who was soon managing the band as well. He used his contacts to swiftly acquire a January 1, 1962 audition at Decca Records that has been heavily bootlegged (some tracks were officially released in 1995). After weeks of deliberation, Decca turned them down, as did several other British labels. Epstein's perseverance was finally rewarded with an audition for producer George Martin at Parlophone, an EMI subsidiary; Martin signed the Beatles in mid-1962.

In August 1962, drummer Pete Best was kicked out of the group, a controversial decision that has been the cause of much speculation since. He was replaced with Ringo Starr (born Richard Starkey), drummer with another popular Merseyside outfit, Rory Storm and the Hurricanes. Starr had been in the Beatles for a few weeks when they recorded their first single, "Love Me Do"/"P.S. I Love You, " in September 1962. Both sides of the 45 were Lennon-McCartney originals, and the songwriting team would be credited with most of the group's material throughout the Beatles' career.

The Beatles phenomenon didn't truly kick in until "Please Please Me, " which topped the British charts in early 1963. This was the prototype British Invasion single--an infectious melody, charging guitars, and positively exuberant harmonies. The same traits were evident on their third 45, "From Me to You" (a British #1), and their debut LP, Please Please Me. Although it was mostly recorded in a single day, Please Please Me topped the British charts for an astonishing 30 weeks, establishing the group as the most popular rock 'n' roll act ever seen in the UK.

The Beatles had taken the best elements of the rock and pop they loved and made them their own. Since the Quarrymen days, they had been steeped in the classic early rock of Elvis, Buddy Holly, Chuck Berry, Little Richard, Carl Perkins, and the Everly Brothers; they'd also kept an ear open to the early '60s sounds of Motown, Phil Spector, and the girl groups. They added an unmatched songwriting savvy (inspired by Brill Building teams such as Gerry Goffin and Carole King), a brash guitar-oriented attack, wildly enthusiastic vocals, and the embodiment of the youthful flair of their generation, ready to dispense with post-war austerity and claim a culture of their own. They were also unsurpassed in their eclecticism, willing to borrow from blues, popular standards, gospel, folk, or whatever seemed suitable for their musical vision. Producer George Martin was the perfect foil for the group, refining their ideas without tinkering with their essence. During the last half of their career, he was indispensable for his ability to translate their concepts into arrangements that required complex orchestration, innovative applications of recording technology, and an ever-widening array of instruments.

Just as crucially, the Beatles were never ones to stand still and milk formulas. All of their subsequent albums and singles would show remarkable artistic progression (though never at the expense of a damn catchy tune). Even on their second LP, With the Beatles (1963), it was evident that their talents as composers and instrumentalists were expanding furiously, as they devised ever more inventive melodies and harmonies, and boosted the fullness of their arrangements. The 1963 singles "She Loves You" and "I Want to Hold Your Hand" established the group not just as a successful pop act, but as a phenomenon never before seen in the British entertainment business, as each single sold over a million copies in the UK. After some celebrated national TV appearances, Beatlemania broke out across the British Isles in late 1963, the group generating screams and hysteria at all of their public appearances, musical or otherwise.

Capitol, which had first refusal of the Beatles' recordings in the United States, had declined to issue the group's first few singles, which ended up appearing on relatively small American independents. Capitol took up its option on "I Want to Hold Your Hand, " which stormed to the top of the US charts within weeks of its release on December 26, 1963. The Beatles' television appearances on "The Ed Sullivan Show" in February of 1964 launched Beatlemania (and the entire British Invasion) on an even bigger scale than it had reached in Britain. In the first week of April 1964, the Beatles had the top five best-selling singles in the US; they also had the top two slots on the album charts, as well as other entries throughout the Billboard Top 100. No one had ever dominated the market for popular music so heavily; it's doubtful than anyone ever will again. The Beatles themselves would continue to reach #1 with most of their singles and albums until their 1970 breakup.

1964's A Hard Day's Night, a cinema verite-style motion picture comedy/musical, cemented their image as the Fab Four--happy-go-lucky, individualistic, cheeky, funny lads with nonstop energy. The soundtrack was also a triumph, consisting entirely of Lennon-McCartney tunes, including such standards as the title tune, "And I Love Her, " "If I Fell, " "Can't Buy Me Love, " and "Things We Said Today." Between riotous international tours in 1964 and 1965, the Beatles continued to pump out more chart-topping albums and singles. (Until 1967, the group's British albums were often truncated for release in the States; when their catalog was transferred to CD, the albums were released worldwide in their British configurations.) In retrospect, critics have judged Beatles for Sale (late 1964) and Help! (mid-1965) as the band's least impressive efforts. To some degree, that's true. Touring and an insatiable market placed heavy demands upon their songwriting, and some of the originals and covers on these records, while brilliant by many groups' standards, were filler in the context of the Beatles' best work. The best songs from this period, however, show the group continuing to move forward, especially the singles "I Feel Fine, " "She's a Woman, " "Ticket to Ride, " and "Help!, " which boast increasingly intricate guitar sounds and clever lyrics.

Although the Beatles' second film, Help!, was a much sillier and less sophisticated affair than their first feature, it too was a huge commercial success. By this time, though, the Beatles had nothing to prove in commercial terms; the remaining frontiers were artistic challenges that could only be met in the studio. They rose to the occasion at the end of 1965 with Rubber Soul, one of the classic folk-rock records. Lyrically, Lennon, McCartney, and even Harrison (who was now writing some tunes on his own) were evolving beyond boy-girl scenarios into complex, personal feelings. They were also pushing the limits of studio rock by devising new guitar and bass textures, experimenting with distortion and multi-tracking, and using unconventional (for rock) instruments like the sitar.

The "Paperback Writer"/"Rain" single found the group abandoning romantic themes entirely, boosting the bass to previously unknown levels, and fooling around with psychedelic imagery and backwards tapes on the B-side. Drugs (psychedelic and otherwise) were fueling their already fertile imaginations, but they felt creatively hindered by their touring obligations. Revolver, released in the summer of 1966, proved what the group could be capable of when allotted months of time in the studio. Hazy hard guitars and thicker vocal arrangements formed the bed of these increasingly imagistic, ambitious lyrics; the group's eclecticism now encompassed everything from singalong novelties ("Yellow Submarine") and string quartet-backed character sketches ("Eleanor Rigby") to Indian-influenced swirls of echo and backwards tapes ("Tomorrow Never Knows").

For the past couple of years, live performance had become a rote exercise for the group, tired of competing with thousands of screaming fans that drowned out most of their vocals and instruments. The final concert of their 1966 American tour (in San Francisco on August 29, 1966) would be their last in front of a paying audience, as the group decided to stop playing live in order to concentrate on their studio recordings. This was a radical (indeed, unprecedented) step in 1966, and the media was rife with speculation that the act was breaking up, especially after all four Beatles spent late 1966 engaged in separate personal and artistic pursuits. The appearance of the "Penny Lane"/"Strawberry Fields Forever" single in February 1967 squelched these concerns. Frequently cited as the strongest double-A-side ever, the Beatles were now pushing forward into unabashedly psychedelic territory in their use of orchestral arrangements and mellotron, without abandoning their grasp of memorable melody and immediately accessible lyrical messages.

Sgt. Pepper, released in June 1967 as the Summer of Love dawned, was the definitive psychedelic soundtrack. Or, at least, so it was perceived at the time: subsequent critics have painted the album as an uneven affair, given a conceptual unity via its brilliant multi-tracked overdubs, singalong melodies, and fairy tale-ish lyrics. Others remain convinced, as millions did at the time, that it represented pop's greatest triumph, or indeed an evolution of pop into art with a capital A. In addition to mining all manner of roots influences, the musicians were also picking up vibes from Indian music, avant-garde electronics, classical, music hall, and more. When the Beatles premiered their hippie anthem "All You Need Is Love" as part of a worldwide TV broadcast, they had been truly anointed as spokespersons for their generation (a role they had not actively sought), and it seemed they could do no wrong.

Musically, that would usually continue to be the case, but the group's strength began to unravel at a surprisingly quick pace. In August 1967, Brian Epstein--prone to suicidal depression over the past year--died of a drug overdose, leaving them without a manager. The group pressed on with their next film project, Magical Mystery Tour, directed by themselves; lacking focus or even basic professionalism, the picture bombed when it was premiered on BBC television in December 1967, giving the media the first real chance it had ever had to roast the Beatles over a flame. (Another film, the animated feature Yellow Submarine, would appear in 1968, although the Beatles had little involvement with the project, either in terms of the movie or the soundtrack.)

Judged solely on musical merit, The White Album, a double LP released in late 1968, was a triumph. While largely abandoning their psychedelic instruments to return to guitar-based rock, they maintained their whimsical eclecticism, proving themselves masters of everything from blues rock to vaudeville. As individual songwriters, too, it contains some of their finest work (as does the brilliant non-LP single from this era, "Hey Jude"/"Revolution").

But by the White Album, it was clear (if only in retrospect) that each member was more concerned with his own expression than that of the collective group. In addition, George Harrison was becoming a more prolific and skilled composer as well, imbuing his own melodies (which were nearly the equal of those of his more celebrated colleagues) with a cosmic lightness. Harrison was beginning to resent his junior status, and the group began to bicker more openly in the studio. Ringo, whose solid drumming and good nature could usually be counted upon (as was evident in his infrequent lead vocals), actually quit for a couple of weeks in the midst of the White Album sessions. Apple Records, started by the group earlier in 1968 as a sort of utopian commercial enterprise, was becoming a financial and organizational nightmare.

These weren't the ideal conditions under which to record a new album in January 1969, especially when McCartney was pushing the group to return to live performing, although none of the others seemed especially keen on the idea. They did agree to try and record a "back-to-basics, " live-in-the-studio-type LP, the sessions being filmed for a television special. Harrison enlisted American soul keyboardist Billy Preston as kind of a fifth member on the sessions, both to beef up the arrangements and to alleviate the uncomfortable atmosphere. In order to provide a suitable concert-like experience for the film, the group did climb the roof of their Apple headquarters in London to deliver an impromptu performance on January 30, 1969, before the police stopped it; this was their last live concert of any sort.

Generally dissatisfied with these early 1969 sessions, the album and film--at first titled Get Back, and later to emerge as Let It Be--remained in the can as the group tried to figure out how the projects should be mixed, packaged, and distributed. A couple of the best tracks, "Get Back"/"Don't Let Me Down, " were issued as a single in the spring of 1969. By this time, the Beatles' quarrels were intensifying in a dispute over management: McCartney wanted their affairs to be handled by his new father-in-law, Lee Eastman, while the other members of the group favored a tough American businessman, Allen Klein.

It was something of a miracle, then, that the final album recorded by the group, Abbey Road, was one of their most unified efforts (even if, by this time, the musicians were recording many of their parts separately). It certainly boasted some of their most intricate melodies, harmonies, and instrumental arrangements. It also heralded the arrival of Harrison as a composer of equal talent to Lennon and McCartney, as George wrote the album's two most popular tunes, "Something" and "Here Comes the Sun." The Beatles were still progressing, but it turned out to be the end of the road, as their business disputes continued to magnify. Lennon, who had begun releasing solo singles and performing with friends as the Plastic Ono Band, threatened to resign in late 1969, although he was dissuaded from making a public announcement.

Most of the early 1969 tapes remained unreleased, partially because the footage for the planned television broadcast of these sessions was now going to be produced as a documentary movie. For the accompanying soundtrack album, Let It Be, Lennon, Harrison, and Allen Klein decided to have celebrated American producer Phil Spector record some additional instrumentation and do some mixing. By that time it was released, the Beatles were no more.

In fact, there had been no recording done by the group as a four-man unit since August 1969, and each member of the band had begun to pursue serious outside professional interests independently via the Plastic Ono Band, Harrison's tour with Delaney and Bonnie, Starr's starring role in the Magic Christian film, and McCartney's first solo album. The outside world for the most part remained almost wholly unaware of the seriousness of the group's friction, making it a devastating shock for much of the world's youth when McCartney announced that he was leaving the Beatles on April 10, 1970. At the end of 1970, McCartney sued the rest of the Beatles in order to dissolve their partnership; the battle dragged through the courts for years, scotching any prospects of a group reunion.

In any case, each member of the band quickly established viable solo careers. Within a short time, it became apparent both that the Beatles were not going to settle their differences and reunite, and that their solo work could not compare with what they were capable of creating together. Despite periodic rumors of reunions throughout the 1970s, no group projects came close to materializing. Any hopes of a reunion vanished when Lennon was assassinated in New York City in December 1980. The Beatles continued their solo careers throughout the 1980s, but their releases became less frequent, and their commercial success gradually diminished, as listeners without first-hand memories of the combo created their own idols.

Legal wrangles at Apple prevented the official issue of previously unreleased Beatles material for over two decades (although much of it was frequently bootlegged). The situation finally changed in the 1990s, after McCartney, Harrison, Starr, and Lennon's widow Yoko Ono settled their principal business disagreements. In 1994, this resulted in a double CD of BBC sessions from the early and mid-'60s. The following year, a much more ambitious project was undertaken: a multi-part film documentary, broadcast on network television in 1995, and then released (with double the length) for the home video market in 1996, with the active participation of the surviving Beatles.