The initials U R L stand for Universal Resource Locator. This is the shortest, fastest way to refer to the website address you see in your web browser's address bar.
The URL could be a basic domain name like http://www.tacori.com, or it can be longer including file names like
Notice that I said "http://" as part of the URL. Officially a URL is not accurately stated unless you include the http:// part of the web address. Without the http:// you would just be stating a domain name and not a "URL."