Bit.ly is a URL shortening service. This tool is very helpful especially on sites like twitter where there is a character limit of 140 chars then you cant post long urls with description so you can use Bit.ly service which shortens your urls. The shortened URLs when cliekced redirects you to the longer link.

Facebook and twitter are two of the many platforms where people share their favourite links among their network. Tinyurl is another good url shortner but bit.ly is better than tinyurl as it also displays the number of clicks the shortened url received along with where it is being shared.

Bit.ly was the default url shortner for twitter and many other services like tweetd deck also use bit.ly to shorten links.

Today many link shortening services are available but bit.ly is by far the best of them all