A look at the rules in some Olympic sports
A look at the rules and scoring for some Olympic sports:
Team and individual medals are awarded for each of the three Olympic equestrian disciplines. Men and women riders compete directly against each other. International-level horses are specialists and don't cross-enter events.
-Dressage uses standard tests divided into movements, each scored from 0-10 by judges placed around the arena. Total marks are converted to a final percentage score. Three riders make up a team, and all scores count. A further freestyle ride, scored on both compulsory and artistic elements much like figure skating, determines individual medals.
-Show Jumping is contested in an arena over huge obstacles. Teams include four riders, and one score is dropped. Riders are penalized if their horse knocks down or refuses a jump or exceeds a time limit. In the case of ties, there is a jump-off.
-Eventing includes an easier dressage test and show jumping course but adds a cross-country course that tests speed, endurance and agility over demanding fixed obstacles. Riders are penalized on cross-country for refusals, falls and for exceeding the time limit. Low score wins. Teams include five riders, and two scores are dropped.
It's tough at first to distinguish between fencing's three disciplines - epee, foil and saber. The biggest differences involve the target areas. In epee, the entire body is considered part of the target. In foil, the target area is smaller - from the shoulders to the groin in front and to the waist in back. In saber, the target zone is everywhere above the waist except the hands.
In foil and epee, only the tip can score touches; in saber, the side of the blade can score a touch. Points are recorded electronically, with fencers wearing a jacket that contains metal fibers. One point is scored when the weapon, which also has an electric wire running through it, touches an opponent's jacket and completes the circuit.
Field hockey features 11 players per team, including a goalkeeper. Padded and masked like his ice hockey counterpart, the goalie is the only player allowed to use their hands and feet.
Players use a hooked stick, of which the right side is rounded. There are no left-handed sticks. Goals can be scored from the field within the shooting circle (actually a semi-circle in front of goal), penalty corners, and penalty strokes, which are 1-on-1 with the goalie.
The ball is similar in size and weight to a cricket ball.
Players can be penalized if the ball is raised in the air and is a danger to others.
A regulation match is two 35-minute halves. Extra time is added if necessary, then a penalty shootout if needed.
The Olympic teams are divided into two pools of six. The top two in each pool advance to semifinals. Semifinal winners play for the gold and silver medals. Semifinal losers play for the bronze.
The perfect 10 is gone, but the scoring system in gymnastics is pretty easy to understand. You'll see two scores for each routine: the D score (think difficulty) is the numerical value of the skills in the routine, while the E score (think execution) reflects how well the skills were done. D scores, assigned by a two-judge panel, should range from the high 5s to the high 6s. For the E score, the five-judge panel starts with a 10.0 score, and deducts from there for errors, flaws and violations.
Add the D and E scores together and there's your total. Scores in London should be in the 14s and 15s. If you see a score of 16 or higher, someone did something really, really good. A score of 12 or below? Not so much.
A total of 98 men and 98 women earned spots in London: 12 five-person teams, and 38 additional gymnasts. Qualifying sets the stage for the entire competition at the Olympics, determining who will be vying for medals in the team competition, event finals and the biggest prize of all, the individual all-around.
For the team competition, four gymnasts per team compete on each apparatus during qualifying - balance beam, vault, uneven bars, floor exercise for the women, floor exercise, pommel horse, still rings, vault, parallel bars and high bar for the men - and the lowest score on each apparatus is dropped. The top eight teams move on to the team finals, where scores start from scratch and the format changes.
Each team uses three gymnasts on each apparatus, and all three scores count. You'll sometimes hear this referred to as ''three-up, three-count,'' and it's a high-risk, high-reward format. Break out the tough, big-scoring routines, and a spot on the podium could be yours. Make a mistake or two, and you can kiss your medal goodbye.
The 24 gymnasts with the highest individual scores in qualifying advance to the all-around finals, with a limit of two per country. The top eight gymnasts on each event in qualifying make event finals, also with a limit of two per country. Scoring starts from scratch in both the all-around and event finals.
Team handball is played on a 40 by 20-meter indoor court, the largest court for any Olympic indoor ball sport. One match features two teams consisting of seven players, including one goalkeeper. Players can move all over the court though only the goalkeeper is allowed within the goal line - a half circle 6 meters in front of the goal.
The aim is to throw the ball into the opponent's goal. Each successful attempt is worth one point. The team that scores most points during two periods of 30 minutes playing time wins the match. If it's tied after 60 minutes, an overtime consisting of two five-minute periods is played. If there is still no winner, the teams move to a penalty shootout.
The men's and women's tournaments at the London Games each have 12 teams which will be drawn into two groups of six. All teams in one group play each other once. The four best teams in each group advance to the knockout stages, starting with the quarterfinals.
The object of judo is to throw your opponent ''with control and force'' onto their back or to pin them down for 25 seconds, by a stranglehold or arm lock. Either of those moves scores an ''ippon,'' or ten points, which ends the match immediately. Points are awarded by the referee and two judges sitting at opposite corners of the mat, or tatami.
There are various other scores awarded:
-A waza-azari scores seven points and is awarded when fighters almost score an ippon by throwing their competitor onto their back but without control or force, or holding them down for 20 to 24 seconds. Two waza-azari plays constitute an ippon and ends the fight.
-A yuko is worth five points and is typically awarded if a fighter throws their opponent but he or she lands on their side instead of their back. It's also given if judoka hold down their opponents for 15 to 19 seconds.
The aim of judo is to score a superior throw, so points for yuko are not cumulative. For example, a fighter who gets three yuko would lose to an opponent who scores a single waza-azari.
A judo match lasts five minutes. If the score is tied after that, the match goes into a ''golden score'' period where the first player to score wins the fight.
Judo players battle to get a good grip on their opponent's uniform before attempting a throw. They can brush away their opponent's hands, but striking is not allowed. Grabbing their opponent's legs - without having attempted a move to provoke a response first - also is not allowed. Arm locks are permitted, but leg locks are not.