League of Legends: Introduction to Positioning

Melee

Tanks - Champions like Malphite, Alistar, and Amumu. Tanks are usually the ones to initiate the fight and attempt to cause as much disruption in the enemy team as possible. This includes trying to separate the enemy team to minimize their damage and ruin their positioning. Tanks also try to protect their own team, especially their squishies.Tanks often want to be the ones focused on their team so their squishies can have free reign.

Fighters - Champions like Irelia, Garen, and Rumble. Fighters are often durable enough to jump straight into the fray and pursue the target of their choice. They usually help focus a target and try to take down enemy squishies. Fighters prefer to be the focus over

Assassins/Melee Carries - Champions like Akali, Tryndamere, and Master Yi. Assassins are typically squishy, so they have to be careful when they go in. Usually they want to kill all of the enemy squishies first, since they're the biggest threat and fall quickly. Assassins jump in the fight a little after it's started in order to avoid the initial volley of abilities and CC's. If their team gets into a good position, they can also flank the enemy team from the side or behind to hit their backline with ease, and close any escape routes. It's usually a good idea for them to duck out of a fight when focused, then swing back in when they're not in such a threat to finish the job.

Ranged

Casters - Champions like Cassiopeia, Brand, and Ahri. Casters like to stay toward the back lines in order to avoid getting attacked by the enemy team. Casters are quick to follow the initiation of a fight to help crowd control and burst the enemy team, especially the enemy squishies if they can get into range. If a caster can volley their spells onto the enemy squishies early, it greatly tilts the battle in their favor. Casters always try to keep at distance when possible in order to live as long as possible and continue to sling their spells when optimal. Flanking the back line as a caster can often create a nasty situation for the enemies.

Ranged Carry -  Champions like Tristana, Caitlyn, and Graves. Ranged carries are almost always in the back. Since they don't have a lot of burst damage or CC, and most of their damage is steady damage, they need to take full advantage of their range. Ideally they kill the enemy squihshies first, but if it puts them in grave danger, then it's usually better to stay at a safer distance and attack who they can. A dead carry is a useless carry, after all.

Team Positioning

 

Team positioning is very important, especially against certain enemy compositions. If the enemy has Amumu, Malphite, Sejuani, or Alistar, you should avoid standing very close to your teammates. Clumping together tightly will almost guarantee these initiators to CC your entire team, giving the enemy a large advantage at the start of the fight. Similarly, if the enemy team has a Fiddlesticks, try to avoid staying too tightly together when fighting, otherwise he will Crow Storm your entire team.

If the enemy has a lot of single-target assassins, it's sometimes better to stay closer together, making it difficult for the enemy assassin to hop in safely since your entire team can quickly turn to CC and focus them down. Just watch out for assassins such as Katarina or Talon, where they have a large amount of AoE damage.

Keep in mind the type of abilities and crowd control your team and the enemy team has. If they have an Anivia, Karthus, or Rumble, the jungle is usually an area you don't want to fight in. Similarly, if you have one of these champions, you usually want to fight in the jungle to take full advantage of your walls and slows.

Miscellaneous Tips

If you are being chased or focused and you have a Flash or a dash ability, try to move to a wall so you can hop over it when things get too dangerous. This can create a huge positional advantage if you're a ranged character or caster, since melee would have to walk around to reach you.

If you're tower diving, you usually want to let your tanks deal the first hit, or walk in first if there are no friendly minions, so they take tower aggro. This keeps your squishies safe from the tower's attacks, and tanks normally don't get hurt too much from them.

If the enemy has skill shot champions like Ezreal or Nidalee, and a teammate is escaping with really low health, try to save them by standing in between them and the enemy skill shot champion, so they don't get picked off. Similarly, if you're a tank, you can minimize the damage dealt to your team by standing in the way of enemy skill shot champions.

Take advantage of walls if you're ranged. Sometimes the best place to stand is on the other side of a wall and attacking over it, since it keeps you safer.