5 Seconds of Summer are an Australian pop band.Formed in Sydney in 2011, the band consists of Luke Hemmings (lead vocals, guitar), Michael Clifford (guitar, vocals), Calum Hood (bass guitar, vocals) and Ashton Irwin (drums, vocals).They started to gain a small following in 2012 after posting a series of cover versions of popular songs onto YouTube, then rose to international fame when One Direction invited them on their Take Me Home Tour.