Tags
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.
Voting, both in the sense of up or down voting a post, as well as voting to close/reopen or delete/undelete
Each week a Question of the Week is selected and published on the Super User Blog. This tag is for QOTW nominations.
A "tag wiki" is an editable page that briefly summarizes the topic of the tag and that may provide links to existing questions that are often useful to many people.
for questions about the entire network of Q&A sites that make up the Stack Exchange network.
New users are those users who may be new to the Stack Exchange Q&A format, and generally have a low reputation score, which starts from 1 at the time of registration.
HTML links, generally those created within the network on questions, answers, or the site itself.
Questions about the meta site itself (meta.superuser.com)
Unanswered questions are those questions which have no up-voted or accepted answers.
Indicates that the site developers were not able to replicate the behavior reported.