The Barclays Premier League is widely recognised as the world's most-watched and most lucrative football league, being followed, it is estimated, by more than half a billion people in more than 200 countries.

Launched in 1992 and initially composed of 22 clubs, the Premier League was reduced in size in 1995 to 20 clubs, each of which is an equal shareholder. The English Football Association is also a special shareholder and the Premier League comes under the jurisdiction of the FA in some areas of its activities and must submit any rule changes for approval and sanction.

The formation of the Premier League and the link with broadcaster Sky TV saw the start of an era of unprecedented growth in the English game, with more money than ever flooding into football.

The original Sky deal – seen as a radical move at the time, as charging fans to watch televised sport was a new concept – was worth £191 million over five years. The most recent TV rights sale saw Sky and Irish broadcaster Setanta pay a massive £1.7 billion for the right to televise matches until the end of the 2010 season.

The TV money – shared between the clubs – improved and enlarged stadia, higher levels of professionalism and the attraction of some big-money owners have all helped the top Premier League clubs compete on a global scale when it comes to wages and transfer fees.

Premier League clubs are some of the richest in the world, with total club revenues reaching about £1.8 billion in the 2007-08 season. This has led to some of the world's best overseas players and managers coming to England, which has been reflected in their recent domination of the UEFA Champions League.

Currently, the top three Premier League teams go directly into the Champions League, with the fourth-placed club entering a qualifying round. The fifth-placed team progress to the fourth qualifying round of the Europa League – the name for the UEFA Cup from 2009-10 – while the sixth and seventh-placed Premiership sides enter the third qualifying round of the Europa League.

The financial rewards of being in the Premier League are so great that the fight to stay in the top flight becomes more intense with every passing season.

Each year three teams face the drop into the Football League Championship, with the top two from that League making the step up automatically. Those two clubs are joined by the winner of the Championship play-off final - a match that is regarded as the most lucrative single game in world football, as it is worth an estimated £40 million to the winners, which they can earn when they take their place in the Premier League.