[kirant]

Some basics:
- Abilty Power (AP) is used to power your, as the name implies, abilities. That's all it is capable of. For this reason, AP is frequently used to power up characters who's job it is to get in close, drop all the abilities, then run off (often called "Nukes"). The level your abilities are powered up per AP is predetermined and the level that it goes up is criticallly looked at by fans. A low scaling and you're relegated to criticism for being unable to catch up later (often made up for by being able to dominate earlier).
- Attack Damage from items is used to power your automatic attacks. Some characters will also have their abilities improve off of attack damage as well.
- Use the League of Legends Wiki to determine what your character needs. Some have absolutely no need for AP, while some will find little use for AD.
- Look at the character's "stats" assigned to them by the staff. For example, a character like Annie (the girl with the bear) is assigned high "spell" stats, with low "attack" and "defense" stats. This means that she'll be a bigger threat with your abilities than when she physically attacks you. High "Attack" stat means they'll focus on physically bringing you down (auto-attack), high "defense" will likely mean their job will be to outlast you, "spell" means they'll use their abilities to great effect, and high "Difficulty" characters will likely be more of a risk-reward project. Some, such as Lux, don't have the ability to be as consistent or rely on a secondary trait (Lux on timing and precision when aiming, since her abilities don't automatically track targets).
- Crowd Control: Think "debuff" from other games. Crowd control limits your character's ability to do...anything. The key types are stun (unable to move/attack), slow (slower movement speed), and silence (unable to use abilities)
- There are some types of character builds to be familiar with:
-- Melee/Ranged: Pretty obvious stuff. One note is that melee characters often to more damage
-- Carries: A carry is a character expected to have a slower early game, but will effectively win a game at the end (Carry the team on their back). Each team will likely have 3-4 carries, one focussing on spell/ability damage, one on auto-attack damage. These characters often play in the middle lane (where they can level up fast), or in the bottom lane.
-- Tanks: A tank is a character expected to make themselves a threat. Because you can basically ignore an opposing character in a team fight if they aren't a threat, it's a Tank's job to BE a threat. Some, like Rammus, will do this by laying down taunts (forcing them to be attacked), while some will throw down crowd control, or physically block out the screen in one case.
-- Nuke: Effectively your "mage" of the game. Overlaps frequently with the AP carry, a nuke is a character you want to get into combat, drop all your abilities, then hide until you can use your abilities again. These characters often build specifically in AP alone
-- Support: A support's job is to make the rest of their team better. These characters rarely, if ever, play alone in a lane because they don't have high offensive power and can rarely take hits on their own. The use of them is what they can do to other characters. For example, Sona probably won't deal much damage herself (well, that's another story...assume it's true for now), but her abilities can make allies deal more damage, restore their health, and speed them up. The key to a support is always the usefulness of their abilities, not the damage it can deal. The identity of this role fluctuates a bit as there are many ways to "improve" the team. Some use auras to buff the team...some heal the team...one turns other characters into fluffy rabbits! I'm a bit gushy on this role since this is basically my primary style.
-- Jungler: A slightly esoteric role to play. A jungler doesn't use the main game, which is the mooks running out of the base, as experience. Instead, he goes into the forested areas and kills the creeps in the forest for experience. Both teams will have one generally, and it is their job to negate the other jungler and execute ganks. As Caramon mentioned, ganks are effectively assassinations. One character (often either the one in the middle lane or the jungler) will attempt to ambush a champion who's vulnerable (low health, too far ahead, etc)...or at least bully them around.
-- Assassin: A character that relies on cashing in on opportunities. Unable to keep up in a regular fight for whatever reason, an assassin can take down low health targets or beat up on someone out of possition. This job often mixes with junglers as jungling will give you the ability to move into any lane and attempt a gank.

Another key note is to watch when you attack enemy characters. When you do, all AI of the enemy will focus on you. Generally, you're at the bottom of their priority, but this changes if you attack a player. This is dangerous early game as if they hide under a tower, you're going to be eating those shots...and about 4 will kill you.

Some general playing notes:
- Use wards. Mostly a support's job, but wards help you identify where characters are. Not knowing where someone is can kill you easily. For this reason, people often ask you call players. If someone is missing and you think they've gone elsewhere, use the conversation keys to notify them (Often in the form of "[lane] MIA").
- Don't be overzealous in attacking. The closer you are to the other team's towers, the easier it is for someone to sneak in between your tower and theirs and perform a pincer strike (gank).
- Prediction is key. This is something that you'll learn over time, but you can eventually feel when you're too far ahead and are in danger
- Focus on getting money early. Practice "last hitting", or attacking a mook when they are at low HP. Getting items to make you better is key.
- If you have manual aim abilities and are advancing, use them to search bushes. League of Legends has the unique ability to hide in them and people use them as much as possible.
- In the laning phase, avoid death when possible. Lost experience sucks. If you think you can recover lost HP over a little bit of time, but can't risk fighting up front, hide near a turret. Since their HP probably can't eat the shots either, you're a bit safe. If you're really low on HP, use the Recall (B) spell from under the turret (or walk back if you think they'll attack you). Losing a tiny bit of experience is better than dying outright (since killing gives gold and you lose experience anyways when dead)...you'll be back faster, you can spend your money, and you deny them the satisfaction and gold of killing you.
- Buy Boots (the basic ones) early. Movement speed is key in this game.