A Fantasy Sport is a game where a person builds a team comprised of individual players of a professional sport. These team "owners" compete against others based on the individual professionals real statistics. Simple versions of this convert statistics into points earned by each team, then determine the outcome. Other more complicated versions create a computer model of the game by inputting the statistics of each player generated by their professional sport. Examples of fantasy sports are Fantasy Football, Fantasy Baseball, Fantasy Hockey, etc.

Fantasy Football is played by football fans who assemble a team of real NFL players with their real statistics. These teams join a league of from 8-12 teams, then compete throughout a regular season. Often these leagues even have playoffs at the end of the season. A typical roster is made up of 2 quarterbacks, 3 running backs, 5 wide receivers, 2 tight ends, 2 placekickers, and 2 defenses. Points are scored similar to real football, with excess points added for running or passing for many yards at a measure , and points subtracted for turnovers.

Fantasy Baseball has a very similar format to Fantasy Football, with players who manage baseball teams made up of real life baseball players. It is the earliest form of Fantasy Sports, with origins in a form called "tabletop baseball". This form of Fantasy Baseball was made up from customized baseball cards with stats from recent seasons. Players then made up fantasy teams from these cards and played imaginary baseball games against each other. Tabletop baseball evolved into a form called Rotisserie Leage Baseball, where stats were taken from the current season and events such as injuries we are counted into the game. Methods of choosing players for a team include an auction, where players pay for which professionals they want, or a round-robin draft until teams are filled.

Fantasy Hockey is similar to the other popular versions of Fantasy Sports. Players are chosen from real NHL players. A typical Fantasy Hockey team is made up of 2 centers, 2 left wings, 2 right wings, 4 defensemen, and 2 goalies. Two types of leagues are Head-to-Head, where owners play one on one games each week, and Rotisserie, where all owners are trying to win the most amount of points, with no weekly competition.

Fantasy Sports online has grown into a huge business, creating over $100 million in revenue. Over 30 million Americans play fantasy sports. Each year the number of internet leagues and websites grows substantially.