Spam

Spam (in the electronic sense, not the food) has several definitions according to context, mostly derogatory. All share the key property of excessive repetition, either over time or across multiple subjects. "Spamming" is the act of generating spam, and "spammers" are those who do so.

Social spam
"Spam" in game usually refers to messages or other types of communication being sent in volume or frequency much higher than is warranted.
 * In an attempt to find members for raids or other types of group content, players may send LFM or LFG requests repeatedly. WTB/WTS messages for trading or crafting services may be used similarly. As long as the interval between messages is not too high, these types of "spams" are considered acceptable because of the nature of Trade chat and how fast messages can fly by.
 * Sending an overly repeated message or large useless quantity of text in a chat channel is never acceptable. This can be reported to Blizzard by using the "Report Spam" button when right-clicking a player's name in the chat box.
 * Advertisers selling gold farming services, power leveling services, etc. may send whispers to a large number of people anywhere in the game. Spammers may also utilize the in-game mail system as another medium of advertising their services.
 * Sending unexpected invites to guilds or parties to large numbers of people is generally considered spamming, although it is more rude than illegal.

Popular spamming subjects
Gold farmers are responsible for a large amount of spam. As their name implies, they sell gold to players. They generally advertise on level one characters (generally orcs or humans, the natives of the most populated cities of each faction). Most gold sellers have names made up from random letters (Hbvfwaer, Hyeftr, etc.) Both purchasing and selling gold or other in-game items using real-world currency is explicitly against the Blizzard Terms of Use and can result in bans and legal action by Blizzard.

Some spam may take the form of a meme, a joke or other message that has taken on meaning or acceptance within a community. The exact form of such messages may vary from server to server. Often, one person may post a single message in a channel and others will reply with variations. They may be viewed as harmless or entertaining community building activities, or as "trolling" that is irritating or outright harmful to gameplay due to the distraction from intended use of the chat. Three of the most common memes are:
 * A particular item link, repeated frequently. The level 70 dagger Dirge and the legendary Thunderfury, Blessed Blade of the Windseeker are popular subjects. Posters may try to say something clever along with the link, or just post the link alone.
 * The "Anal" game: Various links, which may include spells, achievements, etc. as well as items, are combined with "anal" or some other word to create an inappropriate phrase.
 * ASCII art: The use of regular text characters posted in a block and arranged very carefully to form an image.

E-mail spam
The existence of e-mail spam, messages sent to many recipients at once by advertisers or hackers, is well known outside of World of Warcraft, and many e-mail services offer filters to remove such messages. Some spam e-mails specifically target World of Warcraft users, so customers are well advised to be aware of possible spam e-mails.

Phishing attempts can occur via e-mail, and Blizzard has a web page devoted to avoiding these attacks. Never share account information over e-mail, and be careful following links from e-mails. It is best to always verify that the message is from battle.net or blizzard.com by checking the message header, or simply go to the website by another route, either following a known bookmark or typing in the URL manually.

Gold sellers and other illegal services may send advertisements via e-mail. As with such requests received via in-game chat, use of these services can not only result in account suspension, but open up an account to hacking attempts.

Ability spam
Sometimes, repeatedly using the same spell or ability in combat is called "spam". A fire Mage might be accused of "spamming Scorch", a Shaman of "spamming Frost Shock" or a Druid of "spamming Moonfire". Spammed spells are usually instant cast or have a low cast time.

The term can also be used to describe correct use of a "filler" ability or to emphasize a tactical point, depending on class design; for instance "spam Soul Fire once the boss is below 25%" or "spam Heroic Strike for six seconds" would mean to increase the priority of those abilities at those times, but not at the exclusion of everything else (which is usually what is meant when the term is used negatively).

The use of this term for combat actions may stem from situations where the combat log records the use of repeated abilities, resulting in a chat window full of identical messages, much the same as would result from intense social spamming.

History and origin
The term "spam" comes from a Monty Python sketch where patrons order from a menu where nearly every course rattled off contains SPAM, a type of processed meat. At several points, they are interrupted by vikings singing the praise of SPAM. This joke itself is a reference to the exclusion of SPAM from World War II rationing regulations, implying many British citizens likely became sick of eating SPAM.

Spam has been used as the butt of jokes for many years. Comedian Jeff Foxworthy described Spam (the food) as, "Stuff Posing As Meat."

Note that "SPAM" is a registered trademark of a type of processed meat. Lowercase "spam", or "Spam" with the first letter capitalized, is what we use when talking about pointless and/or unwanted text.