The URL is an abbreviation for "Uniform Resouce Locator". URL is the address of a web resource like web page, image, file, etc.
In addition, the "link" word is used instead of the URL abbreviation. Please check this link for more information: Wikipedia: URL
URL shortening is a process of creating a new short link instead of a long link. When a visitor clicks the short link a redirection occurs from short link to long link.
Most of the time necessary data is transfered via URL by adding extra parameters to the end of the URL. And links may get too long and complicated to communicate over certain media like SMS, twitter, e-mail, etc. Simply you may fit more links and content in less space with URL shorteners. Especially in the mobile world, short links are easy to copy and share. By using "CUT.LU URL Shortening Service" your URLs are shortened to twenty (20) chars. This makes your links more manageable.
For instance assume that you have a web site. You need to promote your site's link and collect some extra data.
So you come to a result link like this:
You may use this link in your instagram profile but it's too messy and ugly. And URL shortening comes to play.
When you shorten it with CUT.LU you get a shortened URL like this: http://cut.lu/59m3f6. A visitor clicks this link without noticing which data is transfered to target web source.
http://cut.lu/59m3f6 ----> http://weblebici.com/?name=cutlu-sample&source=instagram&campaign=june-2018-campaign&referrerid=12313
This type of information is invaluable to webmasters and companies. Collected data shows where customers are coming from, when they are coming, etc.
Also helps companies to develop better products and webmasters produce more targeted content.