"background" - key terms from Wikipedia

additional background	vocals
background
background	and win means
background	check
background	checks
background	color
background	dancer
background	extinction rate
background	independence
background	investigation
background	knowledge
background	layers
background	lights
background	material
background	music
background	noise
background	painting
background	palette
background	performer
background	plane
background	plate
background	radiation
background	score
background	source
background	stars
background	vocals
background	vocals on half
background	vocals on track
background	vocals on yellow submarine
background	window
best background	score
blue background
book as background	characters
cosmic background
cosmic background	radiation
cosmic microwave background
cosmic microwave background	radiation
criminal background
desktop background
faint reply in the background
family background
fictional background
living in the background
natural background	radiation
professional background	singers
social background
solo and background	vocals
used as background	music
white background
yellow background