In a Head-to-Head League, you square off weekly against another manager in your league. Your opponent each week is determined by the league schedule, which is automatically generated in all leagues and cannot be modified. You each set a lineup based on league requirements, and whoever ends up with the most fantasy points—based on your league settings—wins the game. Weekly results are then tallied into an overall record.
In non-playoff leagues, the team with the best winning percentage wins the championship. In playoff leagues, the top teams have an elimination tournament to determine a winner.
In a Points League, you're shooting to be the highest scorer within your league. The idea is to set a weekly lineup based on league requirements and hope your players collect more fantasy points then anyone else's players. Points are tallied throughout the football season, and the team with the highest total at the end of the year wins the league championship.