for questions about how tags work, the features of tagging, and what are the most appropriate tags for a question. To request a tag change, use retag-request.

Every question asked on Stack Exchange can have up to five tags that categorize the question.

Meta sites have tags that need to be present in the question, which are , , and ; there are also tags that can be added only from moderators, such as , , and , which are shown with a red background.

For more information see the section on tagging in the FAQ.

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