This compilation includes many of Lennon's most popular solo recordings in their original 45 rpm edits. Five of the songs had not been previously issued on an album: "Cold Turkey", "Instant Karma!", "Power to the People", the holiday single "Happy Xmas (War Is Over)" and "Give Peace a Chance". The latter appeared in truncated form, split to begin side one and end side two. Eight of these singles made the Top 40 on the Billboard chart, with "Whatever Gets You thru the Night" going to number 1; five made the top ten in the United Kingdom. "Imagine", never previously released as a single in the UK, was issued as such concurrent to the release of this album. Several of the master tapes were unavailable for the compilation, and dubs from 45 rpm single records were used, some with shorter fadeouts. A later compact disc issue used the original tapes,[specify] restoring the full fadeouts of these songs. The release of the album came less than three weeks after the resolution of Lennon's long-running immigration dispute and the birth of Sean Lennon. The name of the album originates from the Japanese food katsuobushi, a kind of dried fish.