You’ll see on the right-hand side of the teams a number with an “o” or a “u” before it. As you may have already gathered, the “o” stands for over and the “u” stands for under. Even though the over is on the Celtics line and the “u” is on the Mavericks line, it does not matter. They’re written that way for organizational sake and not because either bet is connected to either team. Remember, it only matters that the total score of the game is. One team can score all of the points, and you’ll still win your bet.
The two results above are the no-vig probabilities. If you're sharp, you'll notice that adding 68.57% and 31.43% up together will give you 100%. The extra 2.95% has been removed, so there's no more vig. We can now go to our odds converter and enter 68.57% into the implied probability field. This will give us moneyline odds of -218. If we enter 31.43%, we'll get moneyline odds of +218. The original moneyline market of the Celtics at -240 and the Grizzlies at +210 therefore has no-vig odds of the Celtics at -218 and the Grizzlies at +218.
The money line bet always relates to bets of $100. A favorite will be represented by a negative money line figure such as -180. This means that in order to profit $100 off your winning bet, you would need to risk $180 dollars. But as I’m sure you already know, you can risk any amount you are comfortable with and the payment (should you win) will be in proportion to the odds. For example, a $50 bet on a -180 line would win you $27 dollars.
One important assumption is that to be credited with a win, either team only needs to win by the minimum of the rules of the game, without regard to the margin of victory. This implies that teams in a winning position will not necessarily try to extend their margin—and more importantly, each team is only playing to win rather than to beat the point spread. This assumption does not necessarily hold in all situations. For example, at the end of a season, the total points scored by a team can affect future events such as playoff seeding and positioning for the amateur draft, and teams may "run up" the score in such situations. In virtually all sports, players and other on-field contributors are forbidden from being involved in sports betting and thus have no incentive to consider the point spread during play; any attempt to manipulate the outcome of a game for gambling purposes would be considered match fixing, and the penalty is typically a lifetime banishment from the sport, such is the lack of tolerance for gambling in sport.

Sports betting has been around since 1000 B.C in China, where betting on animal fights was commonplace. In ancient Rome, one could wager on the Gladiatorial games. The idea of betting on sports is as old as organized sport itself. But up until the 1940s, bettors were fairly limited in what kind of bets they could make. The standard system of odds would allow bets on, for example, the 3-1 odds that the Steelers would beat the Browns.