The Beatles were broken up for a little more than three years when the 1962-1966 and 1967-1970 compilations were released in April 1973.

The two-disc sets – known as the Red and Blue albums, respectively – were neither supplements to nor replacements for the band’s other records. They were merely what they appeared to be: collections of great songs by the greatest band that ever walked the earth.

The albums were initially a reaction against a four-record bootleg compilation called Alpha Omega that was sold on TV in 1972. But the Red and Blue albums had the original masters at their disposal, compiled by the Beatles’ manager, Allen Klein. More importantly, they had a handful of cuts – including "From Me to You" and the single version of "Let It Be" – that were never released on the Beatles’ official albums.

But most of all, 1962-1966 and 1967-1970 trimmed the little fat that could be found on the original LPs and gathered 54 of the band’s best songs -- 28 on the former, 26 on the latter, all written by the Beatles -- in one place.

They’re strung together chronologically, starting with 1963’s "Love Me Do" (the Please Please Me album version) and ending with "The Long and Winding Road" from 1970’s Let It Be. Before the CD era, they were the only place to hear many of the single versions of hit songs on something other than scratchy old 45s. The records were an immediate hit. 1962-1966 reached No. 3; 1967-1970 hit No. 1 for one week. Since their release 40 years ago, they’ve sold more than 30 million copies combined.

The compilations have become such a crucial part of the Beatles Capitol catalog that they were reissued on CD in 1993, and they continue to be an excellent starting point for new Beatles fans.

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