In American football, passing, along with running (also referred to as rushing), is one of the two main methods of advancing the ball down the field. Passes are typically attempted by the quarterback, but any offensive player can attempt a pass provided they are behind the line of scrimmage. To qualify as a passing play, the ball must have initially moved forward after leaving the hands of the passer; if the ball initially moved laterally or backwards, the play would instead be considered a running play. In addition to the overall National Football League (NFL) receiving champion, league record books recognize the rushing champions of the American Football League (AFL), which operated from 1960 to 1969 before being absorbed into the National Football League in 1970.