There are 2 kinds of badges--**general** badges, and **tag** badges.

![Screenshot showing badges page, emphasizing the two types.][1]

##General Badges

**General** badges are the kind most frequently discussed. Each one is awarded based on a separate condition. All their names are capitalized and most are a little bit silly.

General badges are never *automatically* revoked. General badges do not express that their holders *continue to meet the requirements to have received them*, only that they met those requirements at one time.

For example, if you earn a [Good Answer][2] badge, that means one of your answers had a score of 25 (that is, 25 upvotes, plus one upvote for every downvote). If your post has a score of 25 and then gets downvoted (or unupvoted), you don't lose your Good Answer badge.

However, a general badge may be *manually* revoked [if you got it by "henious cheating."][3] I believe such removal requires the involvement of a Stack Exchange employee. An example of a badge earned "heniously" is if you get your Good Answer badge by creating 25 additional accounts and use each one to upvote your post. In contrast, if you get your [Critic][4] badge by downvoting something but then removing the downvote, that is not "henious."

##Tag Badges

**Tag** badges reflect your number and distribution of upvotes in a tag in real time, and are automatically revoked when your score drops too low (and are re-awarded later if the necessary score is again met).

For example, [I currently hold the sudo badge][5]. If my total score in that tag dropped below 100, or if it remained at or above 100 but my number of upvoted posts dropped below 20 (as could happen if posts were deleted or if votes were changed), then **I would automatically lose the badge.**

My understanding is that community wiki posts do not contribute to tag badges (though they do contribute to *most* general badges). So previously non-CW posts *becoming* community wiki can also cause tag badges to be lost.


  [1]: https://i.sstatic.net/Mccnc.png
  [2]: http://askubuntu.com/badges/24/good-answer
  [3]: http://meta.stackoverflow.com/a/17854/185080
  [4]: http://askubuntu.com/badges/7/critic
  [5]: http://askubuntu.com/badges/139/sudo?userid=22949