Everyone watches tennis (especially womens tennis, mmmmm), but not everyone thinks to bet on tennis.

Tennis odds don\'t look like the standard wagering numbers weekend football warriors would see, which might be intimidating to rookie bettors.

There are several ways to bet on tennis - head-to-head matchups and total number of sets.

The standard odds on Roger Federer vs. Rafael Nadal might look something like Federer -300, Nadal +240.

It means Federer is favored and that you must risk $300 in order to win $100. If Federer wins, you win your tennis bet, reclaim your $300 stake and win $100 more.

If he loses, you lose your $300.

To bet the underdog Nadal, you only need to wager $100 in order to win $240. It\'s the old risk-reward game. By betting the underdog, you can potentially win a bigger payday.

If Federer was successful in defeating Hass you would collect your $100 win and have your $600 stake returned.

oddsmakers post a line on the number of sets the match should go. A bettor can choose the OVER or UNDER.

There are also point-spread style of tennis betting, where Federer might be shown as -1.5, -150 and Nadal is +1.5, +130. What this means is that Federer must not only win, he must win by at least two sets.

So if he defeats Nadal 3-0 or 3-1, he wins the bet. If Nadal wins or even if he loses 3-2 in sets, Nadal wins the bet (because his 2 + 1.5 = 3.5, which is more than Federer\'s 3).

You can also place tennis bets on future events. For example, you can wager in July on whether you think Federer will win the US OPen in August.

He may be listed as a -150 favorite, whereas Nadal might be +300 and Tommy Haas might be +500.

It means you can wager $150 now on Federer to win $100. And if you like Nadal\'s chances, bet him now for $100 and earn $300 when he wins it all!

Good luck with your tennis betting adventures.