The Brazilian Serie A is the top professional football league in Brazil, featuring 20 teams that compete annually. Established in 1971, it is known for its high level of competition and has produced many talented players who have gone on to achieve international success. The league operates on a system of promotion and relegation with the Campeonato Brasileiro Série B. Each season, teams play 38 matches, facing each other twice, once at home and once away. The team with the most points at the end of the season is crowned the champion, while the bottom four teams are relegated to the lower division.