To allow intermediate HTTP nodes (proxy servers, web caches, etc.) to accomplish their functions, some of the HTTP headers (found in HTTP requests/responses) are managed hop-by-hop whereas other HTTP headers are managed end-to-end (managed only by the source client and by the target web server).
HTTP is an application-layer protocol for transmitting hypermedia documents, such as HTML. It was designed for communication between web browsers and web servers, but it can also be used for other purposes, such as machine-to-machine communication, programmatic access to APIs, and more.
HTTP (Hypertext Transfer Protocol) is a core Internet protocol that defines how data is exchanged between clients and servers on the web. Enables communication between web browsers and web servers.
Basically, HTTP is an TCP/IP based communication protocol, which is used to deliver data (HTML files, image files, query results etc) on the World Wide Web. The default port is TCP 80, but other ports can be used. It provides a standardized way for computers to communicate with each other.
HTTP is the protocol behind nearly all communication on the web. A browser loading a page sends an HTTP request for the HTML document, parses the response, then sends additional requests for stylesheets, scripts, images, fonts, and other subresources.
Hypertext Transfer Protocol (HTTP) is the foundation of the World Wide Web, and is used to load web pages using hypertext links. Learn more about HTTP.
Despite the XML and Http in the name, XHR is used with other protocols than HTTP, and the data can be of many different types like HTML, CSS, XML, JSON, and plain text.