Betting 101: Over/Under
Over: Betting the over means you expect both teams to combine for more points than the point total.
Under: Betting the under means you expect both teams to combine for less points than the point total.
Push: When the combined number of points is equal to the point total then the bet is a push. Sportsbooks return all wagers to bettors and the bet is neither won nor lost. Uneventful at best.
Hook: The sportsbook often adds a half-point (.5) to the end of the point spread or total. This is the hook. The hook eliminates the possibility of a push since there is no way to score half a point, yet.