A URL (Uniform Resource Locator) is the complete web address used to access a specific resource on the internet, such as a web page, image, or file. It consists of several components, including the protocol (e.g., http:// or https://), the domain (e.g., www.example.co.nz), and additional path information (e.g., /page1.html). A domain, on the other hand, is a subset of the URL and represents the unique location of a website within that address.