What is a bounty by Community?

Question

I just got a bounty worth of 25 points. Community, thank you very much!

But I wonder: who can give such bounties and why?

Edit: Aha! These things happened:

1. Someone awarded a bounty to the fondue question.
2. I showed up and gave an answer (but I didn't see the bounty).
3. My answer was upvoted at least two times.
4. The bounty period expired before the bounty has been awarded.
5. The auto-award kicks in, halfs the bounty and awards as user Community.

I think my confusion comes from the fact that I didn't realize a bounty was open, and that I didn't understand user Community. Am I right?

By the way, I tried to click the bounty icon to understand these +25 points... Perhaps clickable bounty icons would be helpful?

Answer 1

I think it basically works like this:

You get half the bounty of the question automatically awarded by the system if you are the most up-voted answer (that has at least a score of 2 and was posted after the bounty was assigned) when the bounty expires and the bounty offerer has not awarded the bounty manually.

There is some info in the stackoverflow.com faq and in the blog, and this question and answer has a good summary.

Answer 2

Just to expand on Sam's excellent answer.

1. Any bounty that is automatically awarded is awarded by "Community". This explains the giver.
2. Any bounty that is automatically awarded is only half the original bounty amount. This explains the 25 instead of 50. (Although, the bounty offerer loses 50 either way).
3. The answer that is automatically awarded is the answer that received the most upvotes (at least 2) after the bounty was created. This explains why you received the bounty instead of the originally accepted answer or the other higher overall scoring answer.