I was expecting it to be a way of taking a URL and converting it to a base64 type of format that is stored on the "url" itself and decoded by a simple web page. I have wanted to try to do this for a while, but never saw down to look for an appropriate encoding that somehow also compresses.

I helped someone design a regular URL shortener in PHP before, they're not complicated to implement with a simple MySQL (or even SQLite) database and any language you're familiar with. I have not taken a stab at writing a client-side shortener yet on the other hand.

Edit: clarifying