The Hypertext Transfer Protocol, or HTTP, is one of the best known and most used internet protocols today. It was originally designed in 1989 by Tim Berners-Leeas a means to publish hypertext documents on a distributed set of servers, today called web servers. Clients, for example web browsers, would be able to fetch these documents using the HTTP protocol. Hyper, meaning beyond in the word hypertext, literally means beyond the text, signifying the possibility to link to other hypertext documents from within the text itself. These referenced documents may in turn reside on other servers. To achieve this, each document, or resource, is assigned a Uniform Resource Locator or URL. This URL is treated as a simple string but contains all the information the client needs to find and download the contents of the resource.

Resources on the web are not necessarily hypertext documents. They can be images, audio, video, binary applications, or more generally, any type of data that can be encoded. Originally, hypertext documents were written in HTML, and could include basic formatting and simple media content, such as images. Later developments allowed for the separation of the overall design of the hypertext document into Cascading Style Sheet, or CSS, documents. Hypertext documents, or web pages as they are now called, would soon be made dynamic with the inclusion of JavaScript documents and the standardization of a Document Object Model, or DOM. Data can be represented in eXtensible Markup Language or XML documents, as JavaScript Object Notation or JSON documents, or any number of different formats.

All technologies related to HTTP in some way are often referred to as web technologies. All resources accessible using HTTP are likewise called the web, the World Wide Web, or WWW. When we talk of web services, we talk of services made available using the HTTP protocol somehow. Popular methods include Simple Object Access Protocol (SOAP) and Representational State Transfer, or REST, sometimes called RESTful web services.