The exact rules being played may depend upon the competition a match is being played in - as some leagues govern their own regulations. Examples of this are the NBA, and college basketball governed by the NCAA. However, the standardised rules for world basketball are those created by FIBA.
Here is a basic guide to some of the must-know rules:
A standard basketball match consists of two teams, each with 5 players on the court at any one time. The only equipment required is a ball, and court - with a 'basket' at each end. The ball can be moved forward through passes, or by dribbling it. However, one of the most important basic rules to remember is that you cannot run with the ball in a game of basketball!
How long does each game last?
This is something which will differ depending on which league or competition a match is played in. Each game in the NBA is made up of four 12 minute quarters. This is different from NCAA games which are made up of two 20 minute halves. FIBA regulations are further different still - they consist of four 10 minute quarters.
If a game is tied at the end, then a period of 'overtime' is played to determine a winner. An 'overtime' period typically lasts for 5 minutes - whoever is leading at the end of this is deemed the winner of the match. If the teams are still tied then further 'overtime' periods are played until one team has a lead.
How are points scored?
Points are scored by a successful shot into the opponents basket. Each successful shot is worth 2 points - or 3 points in the case of a shot taken from beyond the '3-point-arc'. 1 point can be gained for a successful shot from the 'foul-line', after an opposition has committed a rule breach.
Basketball is a very complicated game, with hundreds of complex rules which would be impossible to explain in this very basic guide. For more information about the full rules please visit one of the following links.