Basketball is my favorite to watch and play. I love how most of the time the better team wins but there is always a chance of an upset if the underdog gets hot (like March Madness). Basketball also can be fast paced or slow paced depending on the team execution leading to high or low scoring games. And there is nothing like a buzzer beater to win a game, especially in a playoff or Game 7 scenario. I also like how basketball is a team sport but one player can have a significant impact on the outcome of the game and season.
I also enjoy watching (American) football, baseball, and (playoff) hockey. I will also watch the World Cup (soccer) and the Olympic sports because I like the nationality aspect of those sports.