An NBA moneyline bet allows a bettor to wager on which team will win a game without having to deal with a point spread. A win by any amount will cash the bet regardless of what the spread was.
Instead of a spread there are NBA odds associated with each team to balance out the bet. If you are betting the favorite you will have to lay additional money while an underdog gets a additional winnings if they win outright.
Lakers -170 vs Mavericks +150. In this example the Lakers are -170 to win the game while the Mavericks are +150. You would have to bet $170 to win 100 if you bet the Lakers while for the Mavericks you would win $150 off a $100 bet. The easy way to think about NBA moneylines is the "-" is how much you need to bet to win $100 , while the "+" is how much you win off a $100 NBA bet.