If you want, you can read everything about URL Shortening on wikipedia (i.e. http://bit.ly/bgkuGT or http://d3w.io/9KilxK or http://➡.ws/蔤囦 ) but I would like to shortly (sorry, pun intended) say a couple of things.
The “URL shortener” concept is very simple: take an URL and transform it into another (shorter) URL, then use redirection to go back to the first URL. So what’s the deal? Continue reading URL Shortening