Effective Tags - Bring more attention to your question

• Pick tags that show higher counts in the look-ahead prompts, as they are more likely to make your question appear highlighted for a user on the main page or show up in someone's rss feed.
• At a minimum, try to include at least one very broad tag (i.e., server-2003 or linux) and one other tag to narrow the topic down within that broader category (i.e. SMTP, or Firewall ).
• You are limited to 5 tags, and you are generally better off trying to use all 5 of them (if there are 5 appropriate matches among existing tags).
• Try to use broad tags. For example, you usually want to include the version with the .Net tag rather than the language. While tagging a question linux-ubuntu-9.04 might convey exactly the information you intend (it implies Linux, Ubuntu, and version 9.04 all in one tag), tagging it linux ubuntu ubuntu-9.04 will bring your question lots more attention, since more people will watch the generic Linux and Ubuntu tags. There is of course a trade-off: you used 3 tags to convey the same information you could have done with one. However, it's hard to understate how many more views the generic tags will bring to your question.
• Each tag should stand on its own: if a tag only makes sense when used in a group with other tags, something is wrong. For example, tagging a question as "Windows XP " (two tags) is wrong.

Tagging Don'ts

• Try not to create new tags. If you create a new tag, that tag is guaranteed not to help your question show up on any subscribed rss feeds or interesting tag lists. Again, the look-ahead prompt can help with this. Odds are it also means you're missing an existing tag for that topic that would more-accurately categorize your question.
• Don't try to summarize your question using the tags. The point of tags on ServerFault is to help other interested persons find your question by sorting it into clear, specific categories. This is not the same as indexing or summarizing the question. The differences are subtle, but important.
• Don't use your username for a tag.

Formatting

• Use all lower-case
• Replaces spaces with dashes (-) to combine multiple words into a single word
• Avoid punctuation. This can make it difficult to use the tag in a url
• Ex: Tag "active directory" as "active-directory".
• A number of tags pre-date the guidelines, and are therefore formatted differently. But that doesn't mean you shouldn't follow these rules.
• When naming a tag, think about how someone would google that subject. In most cases this means typing out the full name, but you may also want to use the abbreviation. For example, "DNS" is probably more appropriate than "Domain-Name-System".

Re-tagging

• Do not re-tag a question if you are not going to add value to the question information by doing it.
• Do not re-tag only to change the format of the tag (i.e., serverfault -> server-fault). This is done automatically by the community user.
• Do re-tag questions to use well-known and popular tags that are appropriate for the question.