Besides gaining reputation with your questions and answers, you receive badges for being especially helpful. Badges appear on your profile page, flair, and your posts.

Question Badges

First bounty you manually awarded on another person's question
6 awarded
First bounty you manually awarded on your own question
27 awarded
First bounty you offered on another person's question
11 awarded
Question score of 10 or more
210 awarded
Asked a question with 1,000 views
81 awarded
First bounty you offered on your own question
42 awarded
Asked a question and accepted an answer
328 awarded
Asked first question with score of 1 or more
732 awarded
Asked a question with no votes, no answers, no comments, and low views for a week
15 awarded

Answer Badges

Answer score of 10 or more
158 awarded
Answered more than 30 days later as first answer scoring 2 or more
121 awarded
Answered your own question with score of 3 or more
18 awarded
Answered first question with score of 1 or more
447 awarded

Participation Badges

Completed all user profile fields
810 awarded
Visited an election during any phase of an active election and had enough reputation to cast a vote
Left 10 comments
100 awarded
Earned at least 200 reputation (the daily maximum) in a single day
9 awarded
Followed the Area 51 proposal for this site before it entered the commitment phase
35 awarded
One post with score of 2 on meta
70 awarded
Posted 10 messages, with 1 or more starred, in chat
31 awarded

Tag Badges

You must have a total score of 100 in at least 20 non-community wiki answers to achieve this badge.
6 awarded

Moderation Badges

First flagged post
85 awarded
First rollback
9 awarded
First down vote
101 awarded
Completed at least one review task. This badge is awarded once per review type
150 awarded
Deleted own post with score of 3 or higher
2 awarded
First edit
446 awarded
Edited first post that was inactive for 6 months
21 awarded
First retag
30 awarded
Deleted own post with score of -3 or lower
13 awarded
Approved or rejected 100 suggested edits
3 awarded
Used 30 votes in a day
11 awarded
First up vote
938 awarded
First approved tag synonym
6 awarded
First tag wiki edit
9 awarded
Used the maximum 40 votes in a day
9 awarded

Other Badges

Visited every section of the FAQ (retired)
37 awarded
Shared a link to a question that was visited by 25 unique IP addresses
85 awarded
Read the entire about page
101 awarded