"The Hardest Part" was the second song released as a single from Blondie's fourth album Eat to the Beat in the US, instead of "Union City Blue". It was written by the group's principal songwriting partnership, Deborah Harry and Chris Stein. It was released as a single only in the US to minor success, reaching just #84 in the Billboard Hot 100, most likely because "Call Me" was released the same month.
"The Hardest Part" is the fourth single from Coldplay's 2005 album, X&Y. The song was released to UK radio and download sites on 3 April 2006 and was released internationally on CD in Europe, Japan, Canada, and Australia in May and June 2006. The international version of the single was made available in the UK on 19 June 2006. In France and the French speaking portions of Belgium and Switzerland "What If" was released instead of "The Hardest Part", and a Belgium commercial CD featured the same B-side, "How You See the World" recorded live at Earls Court.
Like the previous single from X&Y, "Talk", had been a tribute to Kraftwerk, "The Hardest Part" was intended by Coldplay as a stylistic nod to R.E.M.. In fact, according to the band, they felt "The Hardest Part" resembled R.E.M.'s 1991 hit "Losing My Religion" so much that they almost left it off the album.
At the band's official site, Coldplay.com, Chris Martin refers to "The Hardest Part" as a "terrible song, good video". He does not give any reason for this statement, other than a short explanation of how the video was recorded.
