This is far and away the most common type of betting in the US and you'll need to learn how to read them when it comes to understanding
sports betting odds. These are used to bet both basketball and football, most commonly. When you're betting "against the spread", you aren't betting on which team will win but rather which team will cover the spread or how much a team must win or lose by.
A point spread is set by oddsmakers to give both teams an equal chance of winning (at least in theory). It's much more complicated than that though.
In sports, when two teams play against each other, one team is usually better than the other. If all you had to do was pick the winner then it wouldn't be that difficult because all you'd do is bet on the better team. However, since there is a point spread involved, this makes it much more equal.
Let's take a look at a real world example that will help us at understanding
sports betting odds. If you were to look online or in the paper, it might look like this:
(112) Atlanta
(113) Cleveland -11 -110
The numbers in parenthesis identify the game. They are used by the sportsbook to keep track and mean nothing in betting terms. Atlanta and Cleveland are the two NBA teams playing. The -110 means you would need to risk $110 to win $100. The -11 is the point spread that Cleveland is favored by and the -110 are the odds for the point spread (risk $110 to win $100).
If you bet on Cleveland and they win the game by 12 or more points then you would win your bet. However, if they win by 10 or less (or lose), then you would lose your bet. The same goes for Atlanta. If you bet on Atlanta and they lose the game by 10 or less (or win the game out right) then you would win your bet. If they lose by 12 or more then you would lose your bet. However, if Cleveland wins by 11, then the game is a push and all bets on both teams would be refunded.
The standard odds for a point spread are -110, as shown above. This means you would risk $110 to win $100. Although you can bet any amount, it's just that $110 to win $100 is simple to calculate. You can bet any amount but you'll still get 11/10 odds.
It's important to know when it comes to understanding sports betting odds that the extra money you have to put up (the $10 between $110 and $100) is called the vig/vigorish or juice. This is basically the sportsbooks commission if you lose the bet. If you win the bet, then you'll get your original wager back, $110, along with the $100 that you won. If you lose the bet, then you will lose the original $110 that you risked.
The vig/juice and point spreads can vary from sportsbook to sportsbook and from game to game, so it is extremely important to shop around at different sportsbooks to make sure you're getting the best price for the game you're wanting to bet. This is a very important aspect when it comes to understanding sports betting odds.