I am new to soccer and am wonderign how they do the playoffs here (MLS) and around the world. The games yesterday between Monoco and Cheslea was AWESOME and I just wondered what the system was. They called it leg 1 but what if there was a tie? Thanks for your help?
It depends what you mean by 'play-off', I guess you mean a knockout game in a tournament? In which case the scenario can vary. In European competitions (Champions League, UEFA Cup) the knockout ties are all played over two legs (up until the final, which is a one-off game at a neutral venue), with each team having one home game. The total score of the two games is then added together to give the final aggregate score. If the scores are level then the 'Away Goals' rule comes into play, which means that a goal scored at the opposing team's ground will count extra. Example: Monaco 3-1 Chelsea. If Chelsea win the second leg 2-0 then the aggregate score will be level at 3-3 but Chelsea will win on the Away Goals rule, having scored at Monaco's ground. Other competitions work differently - for example the English FA Cup has a one-off match in each round, with the venue being the home ground of one of the teams contesting the tie (decided by a random draw). In the event of a draw the games is replayed at the other team's ground, after which - if the result is another draw - the tie is settled by penalties. The semi-finals and final are played at neutral venues. Away goals do not apply. Then there are the play-offs for promotion within the Nationwide League divisions in England, which work more along the lines of European ties. Other countries probably organise their cup competitions differently but that's a rough guide.
In the leagues of every country in Europa no play-off's are played like in the US. Every team just plays all other teams twice (in some countries with not that many teams in the league 3 or 4 times), so for example the Netherlands: there are 18 teams, so everybody plays 34 matches and the nr.1 after this are champions. Cup-competitions vary. There are a few systems. In the Netherlands there are just 1 leg matches. If the game is a draw, there is played 30 min. extra time and after that (if it's still a draw) penalties. In some other countries they have 2 leg matches like the European Cup system.