Basic Guild Features
Guilds have always offered a few basic features such as guild ranks, a members' list and a guild chat. The guild master and officers of the guild may invite players to the guild, promote or demote them and remove them from the guild altogether; any player in the guild may view the list of members and type in the guild chat.
Guild Banks
Guild banks were added to the game in patch 2.3 during the "Burning Crusade" expansion. A guild bank functions the same way as a player's individual bank, although it is more spacious and can hold both items and gold; the guild master and officers of the guild can control which guild ranks have access to depositing and withdrawing items and gold. Using guild banks you can also set your guild members up for "direct deposit" so that when they loot gold they automatically deduct a percentage to go to the guild bank.
Guild Achievements
Guild achievements were introduced to the game with patch 4.0, at the beginning of the "Cataclysm" expansion. Guild achievements cover almost all areas of the game, from professions to dungeons and PVP. When obtained, some achievements will grant members of the guild a reward; rewards can be many things, from profession patterns and heirloom items to mounts and vanity pets.
Guild Reputation
Patch 4.0 also introduced guild reputation to the game. Each individual member of a guild has a reputation level with the guild, varying from neutral to exalted; players can increase their reputation level by completing quests and participating in PVP or PVE events with their guild. Each member's reputation level determines what rewards he may purchase from the guild vendor.
Guild Experience and Perks
Guild experience and perks were introduced in patch 4.0. Guild members can complete quests and participate in guild events to earn experience for the guild; as the guild earns experience, it will increase in level and unlock additional perks for all its members, such as a shorter cooldown on players' hearthstones, faster movement speed or a Mass Resurrection spell.
Guild Challenges
Guild challenges, introduced in patch 4.1, are special tasks that guilds may complete weekly to earn additional gold, experience and achievements. Guild challenges are available for dungeons, raids and rated battlegrounds; they must be completed by a group composed of players belonging to the guild to earn rewards and be counted against the weekly limit.
Guild Finder Interface
Patch 4.1 introduced a Guild Finder interface to the game. Guild leaders can list their guilds in the interface when they are looking for members; players without a guild can apply to any listed guild or simply sign up to appear in a list of players looking for a guild if there is no guild suitable for their needs. The Guild Finder interface allows both guild leaders and players to specify preferred activities, playing times and roles.