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How World of Warcraft Works


World of Warcraft Addons and Mods
The "World of Warcraft" interface options screen
The "World of Warcraft" interface options screen
©2004-2009 Blizzard Entertainment, Inc. All rights reserved. The Burning Crusade is a trademark, and World of Warcraft and Blizzard Entertainment are trademarks or registered trademarks of Blizzard Entertainment, Inc. in the U.S. and/or other countries.

"World of Warcraft" has lots of ways for you to customize your game. You can access lots of settings through your interface options. These options let you change how your camera moves, which features your game displays and how you use your mouse to target yourself or enemies. Your video options lets you change the level of detail in the game world, which can help compensate for a slow processor or limited graphics abilities.

But suppose you want to completely change the way your party's health and mana bars look when you're in a group or see how much money you have without opening your backpack. The WoW interface options can't handle these requests -- but third-party addons can.

Addons are downloadable additions to "World of Warcraft" that players create. You can find addons at sites like Curse, WowAce and WowInterface. Here are some popular addons and what they do:

  • Omen is a threat meter. "World of Warcraft" mobs attack group members based on how threatening they are. Tanks, who can absorb a lot of damage, need to have the highest threat level in a group. Omen shows players how much threat they're generating relative to the other group members who have the addon installed. Another threat meter is KLH ThreatMeter. The game interface gives players some information about their threat levels as well.
  • Auctioneer keeps track of prices at the in-game auction house. It suggests prices for items you want to sell and helps you figure out whether items you hope to buy are listed at a reasonable price.
  • Atlas displays maps of dungeons and flight paths, which aren't included in the standard game.
This user interface has addon bars at the top and bottom as well as windows for measuring damage and threat.
This user interface has addon bars at the top and bottom as well as windows for measuring damage and threat.
©2004-2009 Blizzard Entertainment, Inc. All rights reserved. The Burning Crusade is a trademark, and World of Warcraft and Blizzard Entertainment are trademarks or registered trademarks of Blizzard Entertainment, Inc. in the U.S. and/or other countries

Addons are created using the Lua scripting language. When you download them, they look like folders full of files. Some files are LUA format, while others are extensible markup language (XML) or table of contents (TOC) files. To install the addon, you simply move its entire folder to the correct location on your computer. These are the default locations:

  • Mac: /Mac HD/Applications/World of Warcraft/Interface/AddOns
  • PC: c:program filesWorld of WarcraftInterfaceAddOns

This makes the addon a part of your game's file structure, which changes how the game operates. You can also download programs that will update your addons for you.

There are a few things to keep in mind if you're using addons:

  • Blizzard doesn't provide technical support for addons. If you have technical issues with the game, the first instruction you'll receive from technical support will probably be to disable your addons.
  • Addons can carry malicious software, like key loggers that capture your username and password, to your computer. Keep your virus protection software up to date, and scan your computer regularly. If an addon tries to force you to install an executable file, don't use it.
  • Your addons may break every time there's a major update to "World of Warcraft." You'll need to download new ones.
  • The people who create addons are basically volunteers. Although many take their work very seriously, they're under no obligation to fix bugs or to update their files.

As long as they don't play the game or make in-game decisions for you, addons don't generally break the rules. Other exceptions are addons that affect the way your computer communicates with a remote server and packet sniffers, or programs that track the way information travels between the client and the server. We'll look at the remote server and how it works in the next few sections.