The Premier League is an English professional league for football clubs. At the top of the English football league system, it is the country's primary football competition. It is contested by 20 clubs, operating a system of promotion and relegation with The Football League. The Premier League is a corporation in which the 20-member clubs act as shareholders. Seasons run from August to May, with teams playing 38 games each. It is sponsored by Barclays Bank, and is therefore officially known as the Barclays Premier League.