Encroachment
ARTICLE 1.
After the ball is ready for play, encroachment occurs when an offensive player is in or beyond the neutral zone after the snapper touches or simulates (hand[s] at or below his knees) touching the ball before the snap (Exception: When the ball is put in play, the snapper is not encroaching when he is in the neutral zone).
Offside
ARTICLE 2.
After the ball is ready for play, offside occurs (Rule 7-1-5) when a defensive player:
Is in or beyond the neutral zone when the ball is legally snapped;
Contacts an opponent beyond the neutral zone before the ball is snapped;
Contacts the ball before it is snapped;
Threatens an offensive lineman, causing an immediate reaction, before the ball is snapped (A.R. 7-1-3-V Note);
Crosses the neutral zone and charges toward a Team A back (A.R. 7-1-5-III); or
Is not behind his restraining line when the ball is legally free-kicked. Offside occurs when one or more players of the kicking team are not behind their restraining line when the ball is legally free-kicked (Exception: The kicker and holder are not offside when they are beyond their restraining line) (Rule 6-1-2).