A bleed is the space around the edge of a page or design the allow for movement and cutting the paper itself. So if a page is 20cm wide the design will be 20.6cm wide to allow a margin of 3mm on each side as a bleed. It prevents the tacky look of a design that is almost to the edge of a page with a thin white area on the edge.
Inhouse printers always have a margin around them – they never print to the edge, so bleeds don’t help and you’ll get white lines around colour bits.
Bleeds are crucial for a good looking document or picture. Without a bleed it leaves it looking incomplete and messy.
