Amnesiac is the fifth studio album by English band Radiohead, released on June 4, 2001 in the United Kingdom and on June 5 in the United States and Canada, debuting at #1 on the UK charts and #2 on the Billboard Top 200. Seen as the furthest departure yet from the arena rock style and heart-on-sleeve songwriting of the band's early career, Amnesiac nevertheless has more audible guitar than its direct predecessor Kid A, and spun off several modestly successful singles. Like Kid A it synthesizes influences of electronic, noise and ambient music.

By resolutely forgetting formula, Radiohead proves itself all the more relevant with Amnesiac.Billboard

the appearance of Amnesiac makes the separation seem arbitrary -- there's no shift in tone, no shift in approach, and the division only makes the two records seem unfocused, even if the best of both records is quite stunning, proof positive that Radiohead are one of the best bands of their time.