Sum 41
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Sum 41 is a Canadian punk rock band from Ajax, Ontario, Canada, active since 1996. The current members are Deryck Whibley (lead vocals, rhythm guitar), Jason McCaslin (bass guitar, backing vocals), and Tom Thacker (lead guitar, backing vocals, keyboard). They've released five studio albums.

Sum 41 released their debut album, All Killer No Filler, in 2001 and achieved mainstream success through the album's first single, "Fat Lip", which reached number-one on the Billboard Modern Rock Tracks chart; it remains the band's most successful single to date. They have since released four more studio albums: Does This Look Infected? (2002), Chuck (2004), Underclass Hero (2007), and Screaming Bloody Murder (2011).

The band was formed by singer-songwriter Deryck Whibley and drummer Steve Jocz, after Whibley convinced Jocz to join his band. Jocz was a drummer in another band and Whibley was convinced that "he was the best drummer around". The duo then added Dave Baksh as lead guitarist a year later and after going through several bassists, ended up picking jason McCaslin to complete their lineup.