It seems like even people who do not bet very often understand what a point spread means and how to bet on one.  Most shops will just force you to lay $11 for every $10 you want to win.  
But, a lot of bettors start to get confused and want to know how to understand American money line odds.  
Today, I’m going to make it easy for you understand this concept and hopefully add another type of wager to your arsenal that will help you build your bankroll.
To illustrate let’s look at an example.  Most places will list three types of odds for a basketball game:
NBA Basketball Spread Money Line Total Points
701 Miami Heat -3.5 -110 -165 o198 -110
702 Orlando Magic +3.5 -110 +145 u198 -110
Each row gives you three possible bets you can make on the game: spread, money line and total points (the over/under). 
The spread and total point columns don’t just list the total and the spread, they also list -110 after. This isn’t by accident.  This is basically where the bet $11 to win $10 comes from.  The line on both the spread and the total is -110 meaning you have to bet $110 to win $100.
The money line column only lists the true American style money line on the game.  These numbers are for who wins the game straight up.  
In the above example you’ll see the Heat are -165 and the Magic are +145.  
If you see a negative number that tells you how much money you must bet to win $100 (this is the favorite) and a positive number means how much risking $100 will win you on the underdog.
For this example that means if you bet $100 on the Magic and Orlando wins, you will win $145 plus the $100 that you wagered.  If your account balance was $100 before your bet, it will be $245 after. 
The return on investment (ROI) on this bet is 145%.  To figure the ROI you take the amount won ($145) / the amount you risked ($100) * 100.  In this case 145/100=1.45*100 = 145%.  
When is taking the Magic a good bet?  When you think they have more than a 40.82% chance of winning the game.  I come to that number by dividing the amount risked ($100) by the amount you get back if it wins ($245).  100/245 = .408163265 or (40.82%).
You can also take the Heat in this situation at -165.  You will have to risk $165 in order to win $100 which would leave you with $265 at the end of the day (your amount risked plus winnings).  
The ROI of a bet on the Heat is 60.6%.  The amount won was $100 / the amount risked $165 which equals 60.6%.  
When would you want to bet on the Heat money line?  When you think they have better than a 62.3% chance of winning the game.  The amount risked was $165 and the amount you get back would be $265 which equals .62264151.
So what is the ROI and breakeven percentages of normal -110 spread bets?  
The ROI would be 100/110 or (90.9%) while the breakeven point is 110/210 (52.381%).  You have to win 52.4% or more of your bets to actually win money in the long run and you need to think you have more than a 52.4% chance of winning your bet in order to place it.
European books use decimal odds which might confuse you if you are used to American style odds, but they are actually quite simple.  
The decimal system just tells you what your payout is for every $1 you bet.  So if the decimal value is 1.909 that means for every $1 you bet you win $0.91 and get $1.91 returned to you.  This is the same as -110 in the American odds format.
After this I hope you feel you are ready to take a stab at money line bets.  They can be a profitable option if you know how to use them.