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.
The question you're asking is designed to solicit opinions or best-practices on a particular topic, with the goal of reaching community consensus.
For questions about tagging questions, creating and deleting tags and tag synonyms.
For discussing whether specific types of questions are allowed on this site or not.
Security Stack Exchange participation in Capture-The-Flag competitions
Questions related to migration, i.e. migrating off-topic questions from the Information Security Stack Exchange site to another site or from elsewhere to this site.
For questions about the /review path where users can view and act on posts by other users that the system thinks may need attention.