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. For example, the URL http://ibrahimjabbari.com/english/index.php/blog/item/407-how-to-create-your-own-branded-url-shortener-without-any-coding can be shortened to http://algr.in/ZkewpP. This is especially convenient for messaging technologies such as Twitter and Identi.ca which severely limit the number of characters that may be used in a message. Short URLs allow otherwise long web addresses to be referred to in a Tweet. In November 2009, the shortened links of the URL shortening service Bitly were accessed 2.1 billion times.