What's your take on parquet?

I'm still reading into it. Why is it closely related to apache? Does inly apache push it? Meaning, if apache drops it, there'd be no interest from others to push it further?

It's published under apache hadoop license. It is a permissive license. Is there a drawback to the license?

Do you use it? When?

I assume for sharing small data, csv is sufficient. Also, I assume csv is more accessible than parquet.