This question already has an answer here:
We all wonder from time to time on which circumstances we get a certain badge. Some ask about it on meta. Then we can point to the list-of-all-badges-with-full-descriptions.
But wouldn't it be best to place the description of every badge where it belongs in the first place?
Copy editor for instance has a lot bigger description than just Edited 500 posts.
And don't get me started on the Epic and Legendard badge: Even some meta posts don't explain the conditions correctly.