It says something about challenges, but then when you read the FAQ it says something about ideas. Which one is it?
Searching for challenges produces 0 results, so it doesn't help with understanding what it is all about eiter.
Searching for challenges produces 0 results, so it doesn't help with understanding what it is all about eiter.
Challenge is a en entity to which you attach your idea, by tagging it with the tag that challenge defined.