Shortening URLs like bit.ly/warningwarning are a bad idea, filling a real need, that seems like it’s not going to just go away.
URLs like mattclare.ca/blog/2010/03/18/warning-about-url-shortening are descriptive, help service like Google but they are way too hard to remember and take a long time to type into a web browser. Services like tinyurl.com , snipurl.com, bit.ly , ow.ly and others provide a short URL that will re-direct users to the longer version.
Google URL shortener is not a stand-alone service; you can’t use it to shorten links directly. Currently, Google URL Shortener is only available from the Google Toolbar and FeedBurner. If the service proves useful, we may eventually make it available for a wider audience in the future.
This was handy a few years ago, and once Twitter took off with its 140 character limit URL shortners took off with it. Most of these services now offer stats on how many clicks a URL has received — perfect for the follower count obsessed Twitterati (I mean that in a positive way – I promise).
The danger with URL shortners is you don’t know where you’re going to end up. With a URL like cbc.ca or mattclare.ca/blog/2010/03/18/warning-about-url-shortening or en.wikipedia.org/wiki/URL_shortening you have some idea of the reputation of that URL before you follow it. You can identify the domain, see if you know it, some times you can determine if you’re going to arrive at a web page, an image or a PDF document, etc. URL shortners obscure all of that.
This problem of this opaqueness was best demonstrated by the phenomenon of rickrolling. A (debate-ably) worse outcome is individuals clicking the short URL could be redirected to a malware/spyware site. While web browsers like Internet Explorer can be compromised just by visiting URLs this is a bad idea!