Hypertext Transfer Protocol

Through the HTTP protocol, resources are exchanged between client devices and servers over the internet. Client devices send requests to servers for the resources needed to load a web page; the servers send responses back to the client to fulfill the requests. Requests and responses share sub-documents -- such as data on images, text, text layouts, etc. -- which are pieced together by a client web browser to display the full web page file.

In addition to the web page files it can serve, a web server contains an HTTP daemon, a program that waits for HTTP requests and handles them when they arrive. A web browser is an HTTP client that sends requests to servers. When the browser user enters file requests by either "opening" a web file by typing in a URL or clicking on a hypertext link, the browser builds an HTTP request and sends it to the Internet Protocol address (IP address) indicated by the URL. The HTTP daemon in the destination server receives the request and sends back the requested file or files associated with the request.