Referer is a common misspelling of the word "referrer"; so common, in fact, that it made it into the official specification of HTTP - the communication protocol of the world wide web. When visiting a webpage, the referer or referring page is the URL of the previous webpage from which a link was followed. More generally, it is the URL of a previous item which led to this request - the referer for an image, for example, is generally the HTML page on which it is to be displayed. The referer is part of the HTTP request sent by the browser program to the web server. HTTP (for HyperText Transfer Protocol) is the primary method used to convey information on the World Wide Web. ... In computing, a protocol is a convention or standard that controls or enables the connection, communication, and data transfer between two computing endpoints. ... Graphic representation of the World Wide Web around Wikipedia The World Wide Web (WWW, W3, or simply Web) is an information space in which the items of interest, referred to as resources, are identified by global identifiers called Uniform Resource Identifiers (URIs). ... A webpage or web page is a page of the World Wide Web, usually in HTML/XHTML format (the file extensions are typically htm or html) and with hypertext links to enable navigation from one page or section to another. ... A Uniform Resource Locator, URL (spelled out as an acronym, not pronounced as earl), or Web address, is a standardized address name layout for resources (such as documents or images) on the Internet (or elsewhere). ... A hyperlink, or simply a link, is a reference in a hypertext document to another document or other resource. ... In computing, HyperText Markup Language (HTML) is a markup language designed for the creation of web pages and other information viewable in a browser. ... Web browser shortcuts on an Apple computer A web browser is a software application that enables a user to display and interact with HTML documents hosted by web servers or held in a file system. ... The term web server can mean one of two things: a computer responsible for serving web pages, mostly HTML documents, via the HTTP protocol to clients, mostly web browsers; a software program that is working as a daemon serving web documents. ...

Many web sites log referers as part of their attempt to track their users. Most web log analysis software can process this information. As referer information can violate privacy, some browsers have the option of disabling this functionality. Some proxy and firewall software will also block referers, to avoid leaking the location of non-public websites. This can in turn cause problems: some servers block parts of their site to browsers that don't send the right referer information, in an attempt to prevent deep linking or unauthorised use of images (bandwidth theft). A web log analysis software (also called a web log analyzer) is a software that parse a log file from a web server (like Apache), and calculate a lot of indicators from values contained in this log file, so indicators about who, when and how a web server is visited. ... Privacy is the ability of an individual or group to stop information about themselves from becoming known to people other than those they choose to give the information to. ... The word proxy can mean more than one thing: a person authorized to act for another person, or upon request by another person (see eg. ... In computing, a firewall is a piece of hardware and/or software which functions in a networked environment to prevent some communications forbidden by the security policy, analogous to the function of firewalls in building construction. ... Deep linking, on the World Wide Web, is the act of placing on a Web page a hyperlink that points to a specific page or image within another website, as opposed to that websites main or home page. ... Bandwidth theft is a label that some apply to the use of bandwidth in potentially unintended ways. ...

Recently many blogs have started publishing referer information in order to link back to people who are linking to them, and hence broaden the conversation. This has led, in turn, to the rise of referer spam. Referer.org is an example of a service that publish referer information. Referer.org automatically removes invalid referers (spam). Referer spam is a kind of search engine-targeted spam. ...

0boting==Reference==

• RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1