UFO are an English rock band that was formed in London in August 1969. They became a transitional group between early hard rock and heavy metal and the new wave of British heavy metal. The band's current lineup includes vocalist Phil Mogg, lead guitarist Vinnie Moore, bass guitarist Rob De Luca, keyboardist and rhythm guitarist Paul Raymond and drummer Andy Parker. They have gone through several line-up changes, leaving Mogg as the only constant member, and had two hiatuses (1983–1984 and again from 1989 to 1991). The band are also notable for featuring former Scorpions guitarist and MSG founder Michael Schenker, who was a member of UFO from 1973 to 1978 and again, occasionally, between 1993 and 2003, when Moore replaced him.

Over a career spanning 48 years, UFO have released 22 studio albums, 14 live recordings, 16 compilation albums and one album of cover songs. They achieved moderate success in the late 1970s and early 1980s with several albums and singles (including their 1979 live album Strangers in the Night) in the UK and US Top 40 charts, and have sold over 10 million records worldwide. Some of their notable songs include "Doctor Doctor", "Rock Bottom", "Natural Thing", "Lights Out", "Too Hot to Handle" and "Only You Can Rock Me".

UFO are considered one of the classic hard rock acts, and have influenced many bands, including Slayer, Testament, The Offspring, Metallica, Iron Maiden, Def Leppard, Megadeth, Tesla, Dokken, Monster Magnet, Voivod, Pearl Jam, Guns N' Roses, Rage Against the Machine, The Smashing Pumpkins, Bigelf, Babylon A.D. and Gun. The band were ranked number 84 on VH1's "100 Greatest Artists of Hard Rock".