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

Asked a well-received question on 30 separate days, and maintained a positive question record
43 awarded
Question favorited by 25 users
26 awarded
Question score of 25 or more
664 awarded
Asked a question with 2,500 views
9.4k awarded

Answer Badges

First to answer and accepted with score of 10 or more
2.8k awarded
Edited and answered 50 questions (both actions within 12 hours, answer score > 0)
14 awarded
Provided non-wiki answers of 15 total score in 20 of top 40 tags
104 awarded
Accepted answer and score of 40 or more
413 awarded
Answer score of 25 or more
1.8k awarded
Answered a question more than 60 days later with score of 5 or more
752 awarded
Zero score accepted answers: more than 5 and 20% of total
16 awarded

Participation Badges

Voted for a candidate in the final phase of an election
843 awarded
Left 10 comments with score of 5 or more
174 awarded
Visited the site each day for 30 consecutive days. (Days are counted in UTC.)
579 awarded
Earned 200 daily reputation 50 times
14 awarded
Voted 10 times, added 3 posts score > 0, and visited the site on 3 separate days during the private beta
46 awarded
10 posts with score of 2 on meta
66 awarded
Posted 10 messages in chat that were starred by 10 different users
46 awarded
Active member for a year, earning at least 200 reputation
5.8k awarded

Tag Badges

You must have a total score of 400 in at least 80 non-community wiki answers to achieve this badge.
108 awarded

Moderation Badges

Raised 80 helpful flags
80 awarded
Voted 300 or more times
357 awarded
Completed at least 250 review tasks. This badge is awarded once per review type
148 awarded
Edited 80 posts
72 awarded
Edited 100 posts that were inactive for 6 months
9 awarded
Up voted 100 answers on questions where an answer of yours has a positive score
32 awarded
Edited 50 tag wikis
4 awarded
Created a tag used by 50 questions
89 awarded

Other Badges

Shared a link to a question that was visited by 300 unique IP addresses
16 awarded