I understand its just like .com but does it have some specific meaning with respect to arduino programming ?
.cc is the TLD for the Cocos Islands. As you might guess, the TLD was not chosen by Arduino for that reason. In this case, .cc is a reference to Creative Commons, to serve as an indication of the open source principles Arduino was founded on.
If not mistaken, youtube started with youtu.be.
You can still put it in a browser and it redirects you to youtube.com.