Before the Web 2.0 technology became popular, there is a popular url service called url forwarding service. But after web 2.0 there is new url service that is called shorten url. In principle, the main goal and functions of both services is to replace the existing url with a new url. It's just give in a different way. When using a url forwarding service you must register first and then choose you own names for new url while shorten url, you can simply enter the url address and let the machine work to choose a name to shorten your url.
Now there are so many services Shorten urls that you can enjoy for free. Each service provides a facility that would spoil the user. There are various factors and reasons why a person using or have used the facility Shorten Url Here are a few reasons.

Shorten the URL Address
This is the main function of Shorten the url, you can shorten a very long url address to a few characters. This of course also be more save space when you include a url that referred to in an email or write in a document
Hiding the Main URL
You'll want to hide your id while promoting the url one affiliate program that you follow where the url is there id you. By using Shorten url then you can minimize a person to directly visit the site you mean without including your id
Easy to Remember
Some Shorten url provide facilities for customized name of the url you want. This is very helpful rather than having to remember a long url address.
Do you have another reason to use Shorten the url? If yes please share with us