In basketball betting, you can wager on if a player will have more or less than a certain number of turnovers in a game.
For instance, a sportsbook may set a player's turnover total at 2.5, and you can bet on whether they will go under or over this total. For instance, let's look at a real line from a game between the Utah Jazz and Cleveland Cavaliers:
Darius Garland, 2.5 Turnovers
Over 2.5 Turnovers, -165
Under 2.5 Turnovers, +135
So, as you can see, the "over 2.5 turnovers" line is the favorite.
This makes sense, as Garland has been averaging a little under 3 turnovers per game in the season.
If you think that Garland is going to have a good night distributing the ball, you'd want to take the Under 2.5 turnovers line, as the potential payout would be $135 in profit for every $100 that you bet.