500px is a photo sharing/sales site that, like any other site or piece of software, needs terms of service. These terms, despite being intended for normal people, are written in impenetrable legalese, which makes them effectively worthless. So, 500px did its users a favor — it translated:
The "basically" rephrasings don't cover everything, but they provide enough of a gist that, when the company has to act on its terms and close an account or pull content, users can't rightly say "I didn't understand the TOS."
Tumblr does this too, and it's just as helpful.
Let's make this a universal thing, eh?