Oasis are an English rock band, formed in Manchester in 1991. Led by lead guitarist and primary songwriter Noel Gallagher and his younger brother, lead vocalist and songwriter Liam Gallagher, they are the most successful group to emerge during the Britpop movement of the mid-1990s. In 2005, The Guinness Book Of Hit Singles And Albums declared Oasis the Most Successful Act of the Last Decade in the UK. and have had eight UK number one singles. The Gallagher brothers are the only remaining original band members, and the present lineup is completed by rhythm/lead guitarist Gem Archer, bass guitarist Andy Bell and drummer Zak Starkey.