A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.
For posts about the use, behavior, or policies related to tags, which are labels applied to questions to group them for search and categorization purposes.
Indicates you've found an erroneous or unexpected behaviour in the system that needs to be fixed.
The Game Development Stack Exchange official chat: generally refers to http://chat.stackexchange.com/rooms/19/game-development
Related to a question flagged for moderator attention, the process of flagging or how flags are handled.