Thanks. :)

Basically it's about the ability to use someones pics if the photographer / artist / author is mentioned. But with certain terms. I think the best explanation can be found from Wikipedia: https://en.wikipedia.org/wiki/Creative_Commons_license

Here's a short version of the license: https://creativecommons.org/licenses/by-sa/4.0/ and from there you find a longer explanation too.

But hey, than you for giving me an idea about what to write a post about next. Or some day. :)