On the other hand, the (-) indicates the favorite and shows you how much you will need to risk to win $100 along with your initial bet. The (+) indicates the underdog and shows you how much profit you get when you bet $100. In most instances, odds are based on a $100 bet and are represented by (–) or (+) in front of numbers. Odds are easy to read, especially in sports like the NFL and NBA. Odds indicate the amount you win in comparison to your bet. The first step is understanding what odds mean. Before making a moneyline bet on any sport, it is important to know how it differs between each.