Popular URL Shortener to Date

We all heard about URL shorter and they're becoming more popular but if you don't have an idea of what is a URL, URL shortening is a technique on the World Wide Web in which a Uniform Resource Locator (URL) may be made substantially shorter in length and still direct to the required page. This is achieved by using an HTTP Redirect on a domain name that is short, which links to the web page that has a long URL.

Here is my top URL Shortener (IMO). I've only listed a few since these are the only one's that i came in contact with, though there are a lot of URL service out there, these are the URL Shortener that i think are the most popular of them all.

1. Bit.ly - is an URL shortening service. The company, Bitly, Inc. was established in 2008. It is privately held and based in New York City. Bitly shortens more than one billion links per month, for use in social networking, SMS, and email.
2. T.co - is Twitter's automatic shortening of all URLs posted on its website.
3. Goo.gl - Google URL Shortener
4. TinyURL - is a URL shortening service, a web service that provides short aliases for redirection of long URLs. Kevin Gilbertson, a web developer, launched the service in January 2002 so that he would be able to link directly to newsgroup postings that frequently had long and cumbersome addresses.