A wie receiver is an offensive position in American and Canadian football. Only players in certain positions are eligible to catch a forward pass. The two players who begin play at the ends of the offensive line are eligible receivers, as are all players in the backfield. Since these two receivers begin play as the offensive players nearest the sidelines, they are referred to as "wide" receivers. At the start of play, one wide receiver may begin play in the backfield, at least a yard behind the line of scrimmage, as is shown in the diagram at the right. The wide receiver on the right begins play in the backfield. Such positioning allows another player, usually the tight end, to also become the eligible receiver on that side of the line. Such positioning defines the strong side of the field. This is the right side of the field in the diagram shown.