difference between a domain name and a url
Domain name and URL are NOT the same thing, though they are often used interchangeably quite like world wide web and the Internet. A domain name is simply a human readable form of an I.P. address while a URL stands for Universal Resource Locator and indicates the location of a file on the Internet.
A domain is a registered name and a website is all the site content including the files (which need to be stored somewhere). Let's use the car analogy. Your domain name is like your license plate. It identifies your site and makes it able to be found on the world wide web. Of course, just like a license plate, a domain name needs to be registered before you can use it.