For the most part, being polite in game is the same as real life.

* When you enter a "room" (chat or vent channel) it's nice to say "Hi!"

* When you leave it's also nice to say "bye" so that people can know that you are leaving, and not just getting kicked.

* Be considerate, treat others as you would like them to treat you.

* Realize that people can't see your face, so if you are joking, let them know.

* Typing in all CAPS is considered shouting. No one likes to be yelled at.


A list of shortened phrases commonly used: (letters are usually lower case)

TY - Thank You
NP - No Problem
LOL - Laugh Out Loud (hehe, or haha sometimes used similarly)
RL - Real Life
BRB - Be Right Back
BBL - Be Back Later
AFK - Away From Keyboard
WB - Welcome back
JK - Joke
BTW - By The Way
IMHO - In My Humble Opinion
BBIAB - Be Back In A Bit

also used:
Alt = Alternate character
Peeps = People
Freeps = Free people
Creeps = Monsters of MPVP (the player verses player in LOTRO)

Glossary (ty Rendalas)
Aggro. This means the monster's "aggression", or who has it's attention. Simply put, who the monster really want to pound on at that moment has the monster's "aggro".

AoE. Area of Effect. These are attacks that affect all enemies within the fixed range or "area of effect".

CC. Crowd Control. This refers to abilities that limit stun or mesmerize opponents, temporarily taking them out of the fight.

Conjunction or Fellowship Maneuver. Occasionally, when a monster is stunned or knocked down, a "wheel" will appear on the screen, with 4 colors to choose from. Each fellowship member chooses his color (his contribution). The sum of these will cause a big effect to happen. Causing large damage to an opponent, healing fellowship members, etc.

Creep. Nickname for monster player. Playing "creep" means playing a monster character in the PvMP zone.

Crit, or Critted item. In crafting, it is possible to "crit" an item: that is, have a critical success that results in a far superior product to the norm. "crit items" are usually "purple items" though at upper levels (47+) they are "teal" or "blue".

DOT. Damage-over-time. This refers to an attack that does, surprise, damage-over-time, like 5 damage every 2 seconds for 20 seconds, for example.

Fellowship quest. A quest that requires a group to complete. Generally far too hard to complete solo, though in rare cases you might be able to solo it.

Freep. Short for "Free Peoples". This term refers to non-monster PCs in the PvMP zone.

FTW. "For the win". Usually used in continuing joke comparative, declaring something superior to something else. For example, in comparing character classes and arguing over which is best, someone who thinks Guardians are the best class might say "Guardian FTW!"

Instance. A private adventure. In an instance, you and your party go into a private encounter where there are no other players to complete an adventure.

Map or Mapping. Every character has a map that they can set to a particular location. Using this map then jumps you back to that location no matter where you are in the game world. Someone who is "mapping" to you is going to use their map to jump to either where you are or somewhere nearby.

Mez. Short for Mesmerized. A "mezzed" opponent is temporarily unable to act, but hitting them or causing any damage will break the mez, freeing them to attack again.

Mob. Common term for monster or enemy. Fighting "multiple mobs" means fighting multiple enemies.

Noob, newb, n00b, newbie, noobie. Term for a newer player. Often derogatory.

NPC. Non-player character. Named characters you may interact with or fight.

Off-. Off- refers to someone who is secondary in that role for a fellowship. The off-tank is the secondary tank, the off-healer is the secondary healer.

PC. Player Character. A character controlled by another player.

Port. To get "teleported" somewhere, usually by the swift travel ability of a hunter.

Pull. To draw an enemy to yourself or the group, beginning a fight.

Purple (Items). These are nice items, more powerful than other items of the same level. A "Purple sword" is a sword that is nicer than most swords of the equivalent level.

PvMP. Player Vs. Monster Player. There is no regular PvP in LOTRO. Instead, you can create a "monster character" to fight against other players as a monster.

PvP. Player Vs. Player: players fighting against other players.

Raid. A large group of 12-24 players. Raids are used to fight through the most difficult areas and against the toughest bosses. "Raiding" means heading to one of these areas with a "Raid". Raids are where the best items in the game are usually found.

Regen. Short for regeneration. Your morale and power "regen" faster out of combat.

Stun.  A stronger form of "mez". A damaging a stunned opponent will not break the stun. Stuns abilities are generally much shorter in duration than mezzes.

Tank. The player who's job it is to keep the monsters aggression (aggro) and take the damage in order to help protect fellowship members. Tanks are usually guardians.

Teal (items, blue items). "Teal" items or "Blue" items are very powerful items (often referred to as "Legendary items", usually only found at upper levels (Level 47+). To be "completely outfitted in blue/teal" means that a character is equipped largely with these very powerful items.

Threat. Threat determines the aggro. The character that causes the highest "threat" to a monster has the monster's attention. An attack that "increases threat" increases the ire that mob has towards you.

Toon. Another term for character. Making a new "toon" means making a new character.