The Primera División is the top professional football league in Spain, featuring 20 teams that compete annually. Established in 1929, it is one of the most prestigious leagues in the world, known for its high level of competition and talented players. The season typically runs from August to May, with each team playing 38 matches. The league operates on a promotion and relegation system with the Segunda División. The teams that finish at the bottom of the Primera División standings are relegated, while the top teams from the Segunda División are promoted. The league's most successful clubs include Real Madrid and FC Barcelona.