URL shortening is a way for users to take long URLs and convert them into something shorter. Typically people use these services as a way to reduce the number of characters of a link to be shared on character-limited channels like Twitter or SMS.
There are various competing URL shorteners and some services offer additional features such as detailed analytics which can give the user an insight into who is following their shortened links.
The use of shortened URLs has increased rapidly over the last few years, mainly due to the growing popularity of Twitter. However, fierce competition between these URL shortening services has created a situation where some services are no longer commercially viable and have gone out of business. The result of this is that URLs shortened using these services no longer work.
What is needed is a non-commerical working group of companies that are prepared to work together to ensure that shortened links continue to work long term. This would help ensure that shortened links can be relied upon and can justify their position as a major facilitator of the real-time web.
310Works.org is absolutely not this organization. In fact, it is a pathetic, confusing and cheap for-profit-please website that aims to take advantage of an honest and simple typo. These guys are douches. If however, you really are interested in the longevity of shortened URLs, we suggest you visit http://301Works.org. 301Works.org was conceived to provide redundancy so that users and services could resolve a URL mapping regardless of availability.