There are literally tons of url shorteners out there now. Facebook was messing with a url shortener at one point. I am not sure if anything ever became of that or not. Google recently started their own url shortener (goo.gl). You have probably heard of bit.ly and tinyurl.com mentioned before. The list goes on and on.
Url shorteners gained popularity with sites like Twitter which has a 140 character limit. So if you have a really long url/link you want to post or include these url shorteners can free up more characters in your post.
One of the things I consider a drawback is you really don't know where that shortened url is going to take you.
For Example this bit.ly shortened url:
Will actually take you to:
But, how do you really know that? Is the person posting the shortened url posting some legit link?
I am actually surprised that people do not end up on some malicious and unwanted sites more often than what they do. I know a lot of people use url shorteners to hide or cloak the actual link for marketing purposes too.
I guess make sure your computer, anti-virus, and any additional protection you have is all up to date.
Url shorteners are definitely handy and convenient for many purposes, posts, and sites around the internet. They just freak me out sometimes when I think about where the link is actually going to take me. But, then again, one could argue the same could be said with just about any regular standard link for that matter.