People keep asking me, What is a leecher? so I thought I should post for some people

We use leecher for the word of a person who tries to get into "lobbies" for free. But Other Definitions Include:

In computing and specifically on the Internet, a leech or leecher is one who benefits, usually deliberately, from others' information or effort but does not offer anything in return, or makes only token offerings in an attempt to avoid being called a leech. In economics this type of behavior is called "free riding" and is associated with the free rider problem.

Depending on context, leeching does not necessarily refer to illegal use of computer resources, but often instead to greedy use according to etiquette: using too much of what is freely given without contributing a reasonable amount back to the community that provides it.

The name derives from the leech, an animal that sucks blood and then tries to leave unnoticed. Other terms are used, such as "freeloader", but leech is the most common.

In games (whether a traditional tabletop RPG, LARPing, or even MMORPG) the term "leech" is given to someone who avoids confrontation and sits out while another player fights and gains experience for the person, or "leecher(S)", who is avoiding confrontation.

* In online multi-player games, "to leech" generally means that a player be present for the presentation of a reward of some sort, without contributing to the team effort needed to earn that reward. In popular MMORPG's the alternative way to refer to a "leecher" has arisen as being "Ninja" (referring to the notional lightning reflexes needed to claim the reward between its appearance and its retrieval by the more deserving player). Most MMOs prevent this by using a "tagging" system (only the player who tags the creature/player/etc. can kill it) and by banning leeching players.

* This is different from "killstealing" where a player uses an attack at the right moment to kill an enemy and take the experience benefit (XP), which may benefit the player or not. In some games, XP is granted to the person who deals a final shot to an enemy, or to who deals a significant amount of damage regardless of who hit it last. Killstealing can in this fashion be applied as a reverse leeching: it prevents another player from gaining XP at all regardless of their effort.

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