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 questions about the favorite question feature or the favorite tags feature.
48 questions
Questions also answered by the user asking, easily marked by the shaded user card attached to the answer.
For questions about the "on hold" status, which used to occur for the first five days that a question is closed.
47 questions
Indicates that the site developers were not able to replicate the behavior reported.
38 questions
Questions about the live Markdown preview of posts as they're being typed.
37 questions
blocked from asking new questions, or posting new answers.
36 questions
For questions concerning citation posts from MSE and citation of other resources when posting here.
35 questions
Cross Posting refers to posting the same question over multiple Stack Exchange sites.
Proposals for new entries for the FAQ repository on this site should use this tag.
34 questions
For requesting clarification on a specific flag. Flagging again with a custom flag may also be an option.
34 questions
For question related to missing context close reason.
For questions related to using various languages on math.SE.
31 questions
For questions both about the built-in editor for this site and also for questions about preparing posts using different programs.
available to users with a reputation of 10000.
28 questions
27 questions
For questions about the user named Community ♦ present on Math.SE (and other Stack Exchange sites.)
27 questions
tag for questions related to some other site from SE network. MathOverflow has its own specific tag (mathoverflow). If you want to ask about a site proposal, use (area51) tag.
27 questions
For questions about the Winter Bash (or holiday hats) to celebrate the end of the year.
26 questions
the Stack Exchange Network staging zone, where users come together to build new Q&A sites. New site ideas are proposed, discussed, and the best go on to beta.
26 questions
the most frequently asked and answered questions on Meta.
26 questions
For questions regarding usernames.
For questions that have as their purpose the celebration of a milestone, either for a specific user or the site.
25 questions
Questions about the "hot questions list" which appears on the main page and truncated on all pages in the SE network, as well as its effect on Math SE.
The black bar across the top of every Stack Exchange site
24 questions
For questions about exporting and printing MSE posts.
24 questions
For issues regarding the help center of Mathematics Stack Exchange.
24 questions
For questions about the mobile versions of Stack Exchange sites. For questions about the mobile apps, use the [android-app] and the [ios-app] tags as needed.
24 questions
Users may only earn a certain amount of reputation each day, with the exception of reputation coming from accepted answers and bounties.
23 questions
For questions about the public lists of changes made to posts by a site's users. They are available for questions and answers by clicking the "edited X min ago" link, and on tag wikis as "history" and…
23 questions
should be used when you are expecting a large number of diverse answers to a question.
23 questions
For questions about, well, questions: how to ask, whether specific questions are appropriate, and so forth.
The Stack Exchange Data Explorer (SEDE), located at data.stackexchange.com, allows you to create and run queries against copies of the databases of popular Stack Exchange sites to investigate trends o…
23 questions
For questions about the copyrights of the StackExchange sites themselves or about the posting of copyrighted material by users.
22 questions
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