Handball is fast and furious
Handball is all about high speed and precise, quick passing - one of the more high octane sports at the Olympics.
The key to success lies in players working together at highg speed to move the ball up the court, and they do so much quicker than their footballing counterparts.
A match lasts for an hour and the speed of the sport means there are frequent goals.
At the last Olympics the match average in both the men's and women's tournament was more than 50 goals-a-game.
This time around 12 teams will contest the men's tournament, with 10 in the women's event.
Group A: Croatia, Iceland, Russia, Slovenia, South Korea & Spain
Group B: Brazil, Egypt, France, Germany, Greece & Hungary
Group A: Brazil, China, Greece, Hungary & Ukraine
Group B: Angola, Denmark, France, Spain & South Korea
The top four teams from each group will advance to the quarter-final knockout stage.
Players rely on feints, body swerves and huge leaps in the air to pass, control the ball and shoot.
It is also a highly physical sport and body-checks can sometimes see players crashing to the ground without any punishment being meted out by officials.
Teams consist of seven players, split three and three in attack and defence, with a goalkeeper at the back.
The three players at the back are the centre, left and right backcourt players who occupy, in footballing terminology, the full-back positions.
Those players also supplement the attacking triumvirate of the central circle runner - who has a free role around the court - and two wingers on the flanks.
The forwards move at speed in an attempt to drag defenders wide and open up space for each other to shoot at goal.
Players can use any part of their body to move the ball, bar their lower legs and feet, and are limited to moving three steps before passing it to a team-mate, unless they opt to dribble with the ball by bouncing it.
Once they stop dribbling they have three seconds to get rid of the ball and, if their feet leave the ground, they must pass or shoot before landing.
Goalkeeper: Only player who can touch the ball with his feet
Centre: Directs play in both defence and attack
Left & right backcourts: Cover circle runner in defence and free-scoring in attack
Circle runner: Creative force in attack and disrupts opponents when in defence
Left & right wingers: Counter opposing wingers and in attack look to create openings
The playing area is 40m by 20m and the goals are two metres high and three metres across.
Two arced lines curve around the goal at six and nine metres. The first delineates the goal area from which all outfield players are prohibited and the second is the free throw line.
When a free throw is awarded for defensive encroachment in the goal area or a foul, all players must stand behind the dashed line while a player takes a penalty throw one-on-one against the goalkeeper from the seven-metre line.