URL stands for Uniform Resource Locator, which is the web address or location of resources on the Internet. A URL consists of the protocol, domain name, and file address. It connects the browser to the specific webpage being requested. There are three main types of URLs: static URLs which do not change content without reprogramming; dynamic URLs which are database-driven and can change; and directory URLs which point to the default file in a directory. URLs are commonly used to locate and access webpages by translating domain names into machine-readable IP addresses.