Today, MLB is composed of 30 teams: 29 in the United States and 1 in Canada. Teams play 162 games each season and five teams in each league advance to a four-round postseason tournament that culminates in the World Series, a best-of-seven championship series between the two league champions that dates to 1903. Baseball games are broadcast on television, radio, and the Internet throughout North America and in several other countries. MLB has the highest total season attendance of any sports league in the world with more than 69.6 million spectators in 2018.