The Collaborative International Dictionary of English v.0.48:

world-wide web \world"-wide` web"\, n.
   The collective total of all computer installations that are
   connected to the internet and provide access to other
   computers connected to the internet, using hypertext
   transfer protocol, to computer files called web pages, which
   may have text, graphics, audio or animated video data, as
   well as pages which may provide data or information in all
   those forms.

   Syn: Web, the web, WWW.
        [PJC]

The Free On-line Dictionary of Computing (30 December 2018):

World-Wide Web

    (WWW, W3, the web) A
   client-server hypertext distributed information retrieval
   system, often referred to as "The Internet" though strictly
   speaking, the Internet is the network and the web is just one
   use of the network (others being e-mail, DNS, SSH).

   Basically, the web consists of documents or web pages in HTML
   format (a kind of hypertext), each of which has a unique URL
   or "web address".  Links in a page are URLs of other pages which
   may be part of the same website or a page on another site on a
   different web server anywhere on the Internet.

   As well as HTML pages, a URL may refer to an image, some code
   (JavaScript or Java), CSS, a video stream or other
   kinds of object.  URLs typically start with "http://",
   indicating that the page needs to be fetched using the HTTP
   protocol or or "https://" for the HTTPS protocol which
   encrypts the request and the resulting page for security.

   The URL "scheme" (the bit before the ":") indicates the
   protocol to use.  These include FTP, the original protocol
   for transferring files over the Internet.  RTSP is a
   streaming protocol that allow a continuous feed of audio
   or video from the server to the browser.  Gopher was a
   predecessor of HTTP and Telnet starts an interactive
   command-line session with a remote server.

   The web is accessed using a client program known as a web
   browser that runs on the user's computer.  The browser
   fetches and displays pages and allows the user to follow
   links by clicking on them (or similar action) and to input
   queries to the server.  A variety of browsers are freely
   available, e.g. Google Chrome, Microsoft Internet
   Explorer, Apple Safari and Mozilla Firefox.  Early
   browsers included NCSA Mosaic and Netscape Navigator.

   Queries can be entered into "forms" which allow the user to
   enter arbitrary text and select options from customisable
   menus and other controls.  The server processes each request -
   either a simple URL or data from a form - and returns a
   response, typically a page of HTML.

   The World-Wide Web originated from the CERN High-Energy
   Physics laboratories in Geneva, Switzerland.  In the early
   1990s, the developers at CERN spread word of the Web's
   capabilities to scientific and academic audiences worldwide.
   By September 1993, the share of Web traffic traversing the
   NSFNET Internet backbone reached 75 gigabytes per
   month or one percent.  By July 1994 it was one terabyte per
   month.

   The World Wide Web Consortium is the main standards body for
   the web.

   Following the widespread availability of web browsers and
   servers from about 1995, organisations started using the same
   software and protocols on their own private internal TCP/IP
   networks giving rise to the term "intranet".

   This dictionary is accessible via the Web at
(http://foldoc.org/).

   An article by John December
   (http://sunsite.unc.edu/cmc/mag/1994/oct/webip.html).

   W3 servers, clients and tools (http://w3.org/Status.html).

   (2017-11-01)