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
10 awarded
First bounty you manually awarded on your own question
10 awarded
First bounty you offered on another person's question
11 awarded
Question score of 10 or more
183 awarded
Asked a question with 1,000 views
338 awarded
First bounty you offered on your own question
13 awarded
Asked a question and accepted an answer
201 awarded
Asked first question with score of 1 or more
354 awarded
Asked a question with no votes, no answers, no comments, and low views for a week
12 awarded

Answer Badges

Answer score of 10 or more
180 awarded
Answered more than 30 days later as first answer scoring 2 or more
110 awarded
Answered your own question with score of 3 or more
20 awarded
Answered first question with score of 1 or more
407 awarded

Participation Badges

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

Tag Badges

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

Moderation Badges

First flagged post
79 awarded
First rollback
18 awarded
First down vote
110 awarded
Completed at least one review task. This badge is awarded once per review type
152 awarded
Deleted own post with score of 3 or higher
6 awarded
First edit
317 awarded
Edited first post that was inactive for 6 months
27 awarded
First retag
33 awarded
Deleted own post with score of -3 or lower
9 awarded
Approved or rejected 100 suggested edits
Used 30 votes in a day
15 awarded
First up vote
550 awarded
First approved tag synonym
5 awarded
First tag wiki edit
12 awarded
Used the maximum 40 votes in a day
10 awarded

Other Badges

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