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.
Indicates you've found an erroneous or unexpected behaviour in the system that needs to be fixed.
for asking questions about closed questions or reopening them.
When a question posted in the main site doesn't concern webmastering and has been closed by a moderator.
Indicates that the reported behavior is intentional and not subject to change