Prop betting seeks to proposition the bettor with a question, one that may or may not have a direct bearing on the final score. For example: How many receiving yards will Tyreek Hill have?
Betting on "Total Under" or "TU" implies that the final result of the selected event must not exceed the aforementioned value. Let's take the "TU 10.5" bet wagered for the number of games in the 1st set of a tennis match.