The World Wide Web is a nonproprietary hypertext document
system that is available on the Internet. The World Wide Web is
commonly confused with the Internet: however, the World Wide Web
is simple a service accessed on the Internet. The World Wide Web
is also referred to as: w3, web, www, and
'the web'. The World Wide Web was the not the first hypertext system,
but, it was the first hypertext system that was successfully interconnected
with the software systems (TCP/IP) of the Internet.
The World Wide Web was designed with the aim of giving users unfettered
access to information, with no centre, and a technological leveling
of hierarchy. Authority became horizontal; earlier information systems
tended to be vertical, with a strong power structure. This, in part,
is due to the World Wide Web supporting unidirectional links: where
a resource can be linked to without the resource having given permission.
Berners-Lee managed to "tie the knot" between hypertext
and the Internet by inventing or co-inventing three technologies:
- HTML (universal hypertext language to
design Web documents)
- HTTP (protocol,
using URLs, to retrieve data from Web servers)
- URLs (unique identifier for documents
hosted on Web servers)
The World Wide Web is designed with a clientserver model;
a client-server model splits the workload between a server (provides
the data) and the client (who requests the data). While the server
will share it's resources with the client, the client simple accesses
the resource, and does not share any of it's resources. Therefore,
the World Wide Web is a system that is comprised of web
servers (computers that host files) and web browsers (client
programs that retrieve the files).
The World Wide Web is named a 'Web' because hypertext documents
(webpages) are connected together - in an system likened to a 'Web'
- through the use of hyperlinks.
Hyperlinks are embedded into hypertext documents (webpages), and
include a URL. Uniform Resource Locators (URLs) are a type of Uniform
Resource Identifier (URI), and are used by the Hypertext Transfer
Protocol (HTTP) to locate the computer a webpage is stored upon.
The World Wide Web is not the only online document retrieval system:
Gopher is an example of another
The World Wide Web was invented by Sir
Tim Berners-Lee. From 1989-1991, Berners-Lee proposed and developed
the software systems of the World Wide Web. Berners-Lee invented
the World Wide Web while he was employed at CERN.
Berners-Lee had attempted to build a document system for CERN in
the early 1980's: the system was named ENQUIRE.
Just as with the World Wide Web, the aim of ENQUIRE, was to help
CERN scientists share information, and to avoid losing information.
Tim Berners-Lee was in the 'right place at the right time' to invent
the World Wide Web. From 1983, the CERN Networking Group - which
included members: Brian Carpenter, Giorgio Heiman, François
Flückiger, Jean-Michel Jouanigot - began to build an internal
and external networking infrastucture. The CERN Networking Group
decided to implement TCP/IP instead of the ISO networking standard,
and by 1991, the CERN external network was a hub for international
Internet traffic. By 1991, it has been claimed that the CERN network
was responsible for handling 80% of Europe's international Internet
traffic. Therefore, CERN was the ideal location to launch a new
Berners-Lee proposed a new 'hypertext project' on the 12st of March,
1989. The proposal paper was named 'a
large hypertext database with typed links'. This proposal was
not successful, and it led to Berners-Lee asking for assistance
from Robert Cailliau to develop
a more 'concrete' proposal. The proposal they developed was named:
Proposal for a HyperText Project' and it was published on the
12th of November, 1990. This proposal was successful, and Cailliau
and Berners-Lee began the development of the software systems for
their new hypertext project.
The project to develop the World Wide Web was originally referred
to as the: CERN WWW Project, and
members of the WWW Project included: Alain Favre, Arthur Secret,
Bebo White, Bernd Pollermann, Carl Barker, Dan Connolly, David Foster,
Eelco van Asperen, James Whitescarver, Jean-Francois Groff, Jonthan
Streets, Nicola Pellow, Peter Dobberstein, Paul Kunz, Pei
Wei, Robert Cailliau, Tim Berners-Lee, Tony Johnson, Willem
Berners-Lee decided that the hypertext documents of the World Wide
Web would be read-only, and accessed by a clientserver architecture
(browsers). The first World Wide Web server (used by Berners-Lee)
was a 'NeXT' computer, and Berners-Lee
developed the first web server software: named CERN
httpd. Since then, there has been a plethora of HTTP server
software, such as Apache, that have simplified
the process of hosting web servers, and have helped to popularise
the World Wide Web.
Berners-Lee was also responsible for designing the first web browser;
unsurprisingly named the: WorldWideWeb. The second browser created
- a version of the WorldWideWeb browser that was ported to several
operating systems - was the Line Mode Browser, and it was designed
by: Tim Berners-Lee, Henrik Frystyk Nielsen and Nicola Pellow. In
1992, Robert Cailliau and Nicola Pellow
developed the first browser for the Macintosh platform: named MacWWW.
Pei Wei, a member of the WWW project - like Cailliau and Pellow
- went on to develop the ViolaWWW hypertext browser.
The World Wide Web was first available as an Internet service on
the 6th of August, 1991: when Berners-Lee released information about
his "Hypertext project" on the newsgroup: alt.hypertext.
However, Berners-Lee had launched the first web server on the 25th
of December, 1990: some simple webpages were available for download,
but only a select number of people knew the project existed at that
On the 30th of April 1993, CERN made the World Wide Web's software
- such as a library of code - publicly available; with the aim of
increasing it's popularity. CERN also announced that the World Wide
Web would be free to use, and no license fee would be charged to
developers (unlike with Gopher: who charged a license fee to host
a server). In 1994, Berners-Lee left CERN and founded the World
Wide Web Consortium (October, 1994). The role of the World Wide
Web Consortium is to create new web standards and promote the compatibility
of web standards for developers.
The World Wide Web was fortunate that it was launched at the same
time that the Internet was being transitioned from a U.S. federally
funded network to a commercial network. By 1995, the World Wide
Web became the Internet's most popular service. By 1997, the popularity
of the World Wide Web spawned the development of large technology
companes - Yahoo!, Paypal, eBay - whose primarily focus was developing
content for the World Wide Web, or, selling products on it. The
growth of Internet use led to the dot
com bubble: where the stocks of Internet companies soared in
value (19972000) and then crashed in value.
HTTP and Internet Protocols
The World Wide Web is a service/application found on the Internet.
The Internet is a system of interconnected computer networks
that use TCP/IP (Internet protocol suite) to communicate. The Internet
protocol suite has four layers and it's highest layer is the application
layer. The Hypertext Transfer Protocol (HTTP) is part of the application
layer of the Internet protocol suite.
The World Wide Web could not function without HTTP. HTTP is a 'request-response'
protocol: which means that one computer sends a request for data
and another computer responds to the request. The World Wide Web
is based upon a client-server computing model: a client application
program (browser), residing on a users computer, will use HTTP to
send a request to retrieve data from a server connected to the Internet.
Files, hosted at a web server, are retrieved
by a client program (browsers) using a Uniform Resource Identifier
(URI). The World Wide Web uses a URI that is named: Uniform Resource
Locator (URL). URL's are embedded within a hyperlink: hyperlinks,
referred to as links, are embedded into webpages (hypertext documents),
and a user simple has to click on a hyperlink and a browser will
use HTTP to locate the resource.
When a client program requests HTTP to locate and retrieve a resource:
HTTP will use another Internet protocol in the process of retrieving
data from a server. HTTP, through a process of encapsulation, uses
protocols in the transport layer of the Internet protocol suite:
most notable the Transmission Control Protocol (TCP). TCP ensures
that data is reliable sent and received by an application layer
protocol. While TCP will use other Internet protocols, HTTP will
be unaware and unconcerned how TCP functions.
The Internet Protocol (IP) is ultimately responsible for the transmission
of data between the computer sending a request and the computer
responding to the request. The Internet Protocol (IP) uses an IP
address (32bit or 128bit number) to identify a host computer and
uses a datagram service to transmit data between IP addresses. TCP
will ensure that IP functions in a reliable 'manner' and no data
packets are lost.
Content on the World Wide Web
If a user wants to upload data to the World Wide Web, then they
need to upload it to a Web server: a web server is a computer connected
to the Internet that allows HTTP to retrieve files from their hard
disk. Users can upload data to web servers hosted by other users,
however, a user has very little control over the data they upload
to such a server.
The most common files uploaded to a web server are webpages (HTML
documents). When a collection of webpages are located at a single
web domain, it is referred to as a website. If a user wishes to
create their own website: then they need to either setup their own
web server or rent space from a third party web server (which can
be either a shared or a dedicated
The majority of people who create a website rent 'space' from a
web hosting company. Once a user has rented
'space' at a web server: then they have the ability to upload files
to the server. If a user wishes to create a website: then they will
need to create webpages (hypertext document) for it. Once a user
has uploaded webpages to a web server: then other Internet users
can access these pages by using a Uniform Resource Locator (URL).
While a URL can use an IP address to loctae a webpage: the problem
with an IP address is that they are difficult to remember. A domain
name is preferable to an IP address: they are easier to remember,
and if a user changes the server they host their data on, then the
data can still be found using the domain name (the domain name will
be tied to an IP address, and the IP address can be changed).
The content of the webpages falls into two broad categories: commercial
and non-commercial. The World Wide Web has spawned many successful
online businesses; which are referred to as e-tailers (e-tailing)
and e-commerce businesses. Some notable e-commerce businesses are:
and Paypal. Some commercial websites
have even launched their own virtual currency, such as Bitcoin.
The world's largest technology corporations are typically located
in Silicon Valley (California);
whereas a number of UK technology companies can be found in Silicon
Privacy and the World Wide Web
While there is no requirement to record the browsing history of
the World Wide Web: typically, the majority of browsing is recorded
to some degree. The World Wide Web is based upon a client-server
model: a client program (browser) requests and retrieves files (webpages,
pictures) from a web server (computer connected to the Internet).
Therefore, whenever a file is requested and retrieved upon the World
Wide Web: the client and the server usually records the session.
When a user requests a file (webpage) from a web server: the server
usually record this request and the IP address of the user requesting
the data. Likewise, the browser (client) of the user will usually
record the data transmission by keeping a copy of the retrieved
files in it's cache (directory) and keeping a record in the history
feature of the browser. The Internet Service Provider - network
the user accesses the Internet with - will typically keep a record
of all the files a user accesses from the Internet. However, the
internal policies of ISP's differ: it is difficult to know precisely
what an ISP will record and store, and for how long. ISP's will
only share their user logs when it is demanded by a legal entity.
Alongside server logs, websites can also record the browsing habits
of it's users by using HTTP cookies
(invented by Louis Montulli).
Cookies are small files, stored on the users computer, that store
information, such as: username authentication, password authentication,
past browsing history. Therefore, if a user returns to a commercial
website - for example eBay - the user will not be required to enter
their username and password again, and the website can serve content
to the user that is related to the content they viewed the last
time they visited the website. Users can delete cookie's whenever
they wish, and the typical (first
party) cookie does not pose a serious privacy risk; especially
if the user has not provided personal identifiable information to
the website. However, tracking cookies,
referred to as third party cookies, can compile a long term record
of a users browsing history - as they record browsing habits at
multiple websites - and are sometimes viewed as malware.
to keep a user's browsing history secret. The problem a user has,
is when they create an account at a website and the account publicly
provides personal details about the user. The most obvious example
is social media websites, like Facebook, where a user will publicly
share their name and location; amongst other personal data. While
social media websites do have privacy settings, the amount of information
a user shares is usually extensive, and the impact it may have upon
a person's privacy and 'real life' is far greater than with other
1. WWW Error Messages:
understand the error messages for unavailable Web pages.