The second number in our example (-110 for both teams) tells you how much you have to wager in order to win $100. It’s an easy way to calculate how much you’ll win if your bet pays off, presented in units of $100 at a time for simplicity’s sake. Most of the time, these two numbers will be the same, because oddsmakers want to set lines so that they get as much action on the underdog as on the favorite, guaranteeing them a profit. If a book gets a single bet of $110 (by a customer hoping to win $100) on the Cowboys and a single bet of $110 on the Giants, it will have taken in $220, but will only have to pay back $210 to whichever customer wins the bet. That’s a guaranteed profit of $10, and since sportsbooks take far more than a single bet in either direction, they stand to earn that seemingly small amount of profit many times over. The $10 difference between what you wager and what you win is known as juice or vig in the sports betting industry, and it’s the way books earn their bread and butter.

With some betting sites odds, certain games are priced differently than risking $1.10 to win $1.00 (which is called -110 odds). For example, you might see the Giants priced at -105 and +7 in a game against the Jets. Now, you only have to risk $1.05 to win $1.00. This is obviously better odds, but it's very likely that they will lose by exactly seven to give you a push. Taking -110 and +7.5 with an alternative bookmaker is actually the better bet.
Identify the type of line you are looking at. All online sports books offer you the chance to have your lines in an "American" or "Money line" version. If I were you, I would use this as my standard. An "American" line uses either a + or - before a number to indicate odds. So a -120 and a +120 are two very different odds on a team… I will explain the differences shortly. Two other less common variations exist: decimal odds and fractional odds. 

Like many high scoring sports, NFL wagering is dictated by the point spread. The spread, or line, is a type of side bet that equalizes the chance of winning a wager. The line offered for any given team will be accompanied with a – or + symbol to indicate whether a team is a favorite or an underdog. The example below displays the spread from the Sports Insights archives at the time of kickoff:
In today's world, patience is a virtue that very few people have left in them. We live in a world with lightning quick internet, instant message and in a world where fast food reigns supreme. People love getting instant gratification. In the sports betting world, that also holds true. It's one thing to sit through a three-and-a-half-hour football game between two mediocre teams only to suffer a bad beat on a completely meaningless last-minute touchdown that does nothing but affect the point spread and burn your ticket. Read More >>
Once the Southeastern Conference gets going on Labor Day weekend, people can bet on the outcome of each game. Or they can make proposition bets on who wins the coin toss, which team will score first and whether the first points will come from a touchdown or a field goal. With proposition bets, fans don’t have to wait until the end of the game to win or lose.
If you're new to football betting and keen to get involved then you've just come to exactly the right place. On this page we will teach you all the basics of betting on football, and make sure that you are on the right track from the moment you place your first wager. If you feel like you're ready to dive right in, here are the top football betting sites we reccomend:
If you bet on the point spread, you’ll often see -110 placed next to each betting option. That means that you have to bet $110 to win $100. The $10 difference is effectively a fee you are paying to place the bet. It can be referred to as the juice or the vig (short for vigorish, which originates from the Russian word for winnings). If there is an even amount of money bet on both sides of the line, the juice guarantees a profit for the house.
Point Spread: The point spread remains the favorite way to wager on pro football, regardless of how many new forms of wagering come on stream. It’s called the line or spread and it’s known as betting ‘sides.’ The common misconception is that Las Vegas sets the spread as its best guess at the margin of victory. But really, it's a number they feel that is a perfect balance and will see an equal number of people to bet the underdog as on the favorite. A negative value like -6.5 means that team is favored by 6.5 points. So deduct 6.5 points from their total score. A positive value on the same game would be +6.5 (add 6.5 points to their final score) and would make that team an underdog of 6.5 points. The favorite must win by at least seven points to cover the spread. The underdog can lose by six points and still cover.