[johnisgood]

> but requires you to contribute source code for changes, additions, and software that you build with it, other than applications.

What does this part mean? Would you please dumb it down for me, perhaps with an example?

[kemitchell]

Keep reading! That is just the Purpose section, which summarizes the license. The specific sections affecting copyleft are Copyleft, Prototypes, Applications, and Contributing. I think they are slightly easier to read and understanding on the master branch of the development repository: https://github.com/kemitchell/api-copyleft-license/blob/mast...

[johnisgood]

> The purpose of this rule is to encourage cooperative development of this software, minimizing duplication of effort across competing substitutes.

Ah, I understand it now! Thank you.