You can shorten URLs to make them easier to share using the Google URL shortener. For example, the short URL http://goo.gl/l6MS takes people to http://googleblog.blogspot.com/2009/12/making-urls-shorter-for-google-toolbar.html.
Below the "Paste your URL here" box, you'll see the long version of your url and the short version. Once created, your link won't expire unless it has to be removed for spam, privacy, or legal reasons.
You can see how many people have clicked on your URL by visiting goo.gl
For more detailed information about the URL's use, including the countries, browsers, and platforms that accessed it, add .info to the end of your short URL. For example, detailed tracking for http://goo.gl/l6MS can be found at http://goo.gl/l6MS.info.
Tracking for all goo.gl short links are publicly visible to all users.
Your links are automatically added to goo.gl where you can track their use.
A unique short URL is created each time a long URL is shortened.
Your links won't show up on your goo.gl page.
The same short URL is reused each time a long URL is shortened by you or someone else.
Report abusive goo.gl short links by filling out a spam report