A flick is also a
slang term for any
photograph of
graffiti.
Flicks are vital to graffiti culture because they are generally the only way of documenting works that often disappear, whether it's under buff paint, or down the tracks into infinity. They are historical documents, and snapshots of style.
Flicks are at the same time prized by both the police, who collect them as evidence, and the graffiti writer, who values them as a priceless visual record. Benchers spend inordinate amounts of time organizing their flicks in albums, trading them, and acquiring them by any means necessary.