Does anybody know what this is ?

This is called a "URL", and when you click it, it takes you to a website. (Naturally, I wouldn't click on an unknown website myself, because it could be full of viruses, spy bots, or even porn! So you can take your own chances and click if you want.)

But again, when you ask "what does it mean", it means it points to a website.

A quick google and I can't find anything but lots of scam warnings. You can do work but can't get your money out at the end.

a scam