All these resources, whether they are static files or dynamically generated in real-time, must be identified using URLs, one for each resource, if they are to be accessible on the web. A URL is a string with the following basic format:
scheme ":" authority[ path ] [ "?" query ] [ "#" fragment ]
The scheme part describes how to interpret the rest of the URL. For communication purposes, you can see this as the means to access and retrieve the resource, or simply put, what communication protocol is being used. For HTTP, this part would be http. For encrypted HTTP, or HTTPS, it would be https.
The authority describes the entity hosting the resource. For HTTP, this would typically be the domain name or IP address of the web ...