is.gd provides you a very
simple easy-to-use API.
This API contains only one function that's used for shortening URLs. Another
good thing is that this function doesn't require any kind of authentication for
users. Therefore, you need just to spam it with your long URL (as you did with
the website.)
This glorious function is
called http://is.gd/api.php,
it accepts only a single argument, longurl,
which can be set to the long URL you need to shorten. When you call the
function, it simply returns the shortened URL as plain text (no more overhead.)
Now, let's try this function.
We'll try to shorten the URL http://JustLikeAMagic.com with
our function. First, connect the arguments, http://is.gd/api.php?longurl=http://JustLikeAMagic.com.
Now copy this address and paste it into your favorite browser. If everything was
OK, you should see the short URL after clicking in the browser toolbar.