Home > Articles > Operating Systems, Server

This chapter is from the book

WWW: World Wide Web

The World Wide Web (WWW, W3, or the Web) provides a unified, interconnected interface to the vast amount of information stored on computers around the world. The idea that created the World Wide Web came from the mind of Tim Berners-Lee of the European Particle Physics Laboratory (CERN) in response to a need to improve communications throughout the High Energy Physics community. The first generation was a notebook program named Enquire, short for "Enquire Within Upon Everything" (the name of a book from his childhood), that he created in 1980 and that provided for links to be made between named nodes. It was not until 1989 that the concept was proposed as a global hypertext project to be known as the World Wide Web. In 1990 Berners-Lee wrote a proposal for a HyperText project, which eventually produced HTML, HyperText Markup Language, the common language of the Web. The World Wide Web program became available on the Internet in the summer of 1991. By designing the tools to work with existing protocols, such as FTP and gopher, the researchers who created the Web created a system that is generally useful for many types of information and across various types of hardware and operating systems.

The WWW is another example of the client/server paradigm. You use a WWW client application, or browser, to retrieve/display information stored on a server that may be located anywhere on your local network or the Internet. WWW clients can interact with many types of servers; for example, you can use a WWW client to contact a remote FTP server (page 408) and display the list of files it offers for anonymous FTP (page 380). Most commonly you use a WWW client to contact a WWW server, which offers support for the special features of the World Wide Web that are described in the remainder of this chapter.

The power of the Web is in its use of hypertext, a way to navigate through information by following cross-references (called links) from one piece of information to another. To use the Web effectively, you need to be able to run interactive network applications. The first GUI for browsing the Web was a tool named Mosaic, released in February 1993. It was designed at the National Center for Supercomputer Applications at the University of Illinois and sparked a dramatic increase in the number of users of the World Wide Web. Marc Andreessen, who participated in the Mosaic project at the University of Illinois, later cofounded Netscape Communications with the founder of Silicon Graphics, Jim Clark. They created Netscape Navigator, a Web client program that was designed to perform better and support more features than the Mosaic browser. Netscape Navigator has enjoyed immense success and has become a popular choice for users exploring the World Wide Web. Important for GNU/Linux users is fact that from the beginning, Netscape has provided versions of its tools that run on GNU/Linux. Also, Netscape created Mozilla (mozilla.org) as an open-source browser project.

Mozilla and the Netscape Navigator24 provide GUIs that allow you to listen to sounds, watch Web events or live news reports, and display pictures as well as text, giving you access to hypermedia. A picture on your screen may be a link to more detailed, nonverbal information, such as a copy of the same picture at a higher resolution or a short animation. When you run Mozilla or Netscape on a system that is equipped for audio, you can to listen to audio clips that have been linked to from a document.

URL: Uniform Resource Locator

Consider the URL http://www.w3.org/pub/WWW. The first component in the URL indicates the type of resource, in this case, http (HTTP—HyperText Transfer Protocol). Other valid resource names, such as https (HTTPS—secure HTTP), and ftp (FTP—File Transfer Protocol), represent information available on the Web, using other protocols. Next comes a colon and double slash (: // ). Frequently the http:// string is omitted from a URL in print, as you seldom need to enter them to get to the URL. Following this is the full name of the host that acts as the server for the information (www.w3.org). The rest of the URL is a relative pathname to the file that contains the information (pub/WWW). Enter a URL in the location bar text box of a Web browser, and the Web server returns the page, frequently an HTML (page 1472) file, pointed to by this URL.

By convention many sites identify their WWW servers by prefixing a host or domain name with www . For example, you can reach the Web server at the New Jersey Institute of Technology at www.njit.edu . When you use a browser to explore the World Wide Web, you may never need to use a URL directly. However, as more information is published in hypertext form, you cannot help but find URLs everywhere—not just online in mail messages and Usenet articles but also in newspapers, advertisements, and product labels.


You might want to consider using Web browsers other than Netscape with your GNU/Linux system. If you do not use the X Window System, try a text browser, such as lynx or links. Mozilla (www.mozilla.org) is the open-source counterpart to Netscape. Mozilla was first released in March 1998 and was based on Netscape 4 code. Since that time Mozilla has been under development by employees of Netscape (now a division of AOL), Red Hat, other companies, and contributors from the community and has released its version 1.0. KDE offers Konqueror, an all-purpose file manager and Web browser (page 286). Other browsers include Galeon (galeon.sourceforge.net), Opera (www.opera.com), BrowseX (browsex.com), and SkipStone (muhri.net/skipstone). Although each Web browser is unique, they all allow you to move about the Internet, viewing HTML documents, listening to sounds, and retrieving files.

Search Engine

Search engine is a name that applies to a group of hardware and software tools that help you find World Wide Web sites that have the specific information you are looking for. A search engine relies on a database of information collected by a Web crawler, a program that regularly looks through the millions of pages that make up the World Wide Web. A search engine must also have a way of collating the information the Web crawler collects so that you can access it quickly, easily, and in a manner that makes it most useful to you. This part of the search engine, called an index, allows you to search for a word, a group of words, or a concept and returns the URLs of Web pages that pertain to what you are searching for.

Many different types of search engines are on the Internet. Each type of search engine has its own set of strengths and weaknesses. You can obtain a partial list of search engines by going to home.netscape.com/escapes/internet_search.html or by clicking the Search button on the Netscape or Mozilla menubar.

Downloading a File

You can use Mozilla, Netscape, or another browser to look at and download a file from an FTP or HTML site. Suppose you enter ftp://ibiblio.org/Linux in the text box of the location bar and press RETURN. After seeing the initial set of directories, click pub (many sites give their public directory this name). You can then click any of the directories (try Linux) to view the available files. Following this example you will find directories named with the classifications of software, documentation, distributions, and more. Each contains a wealth of directories with more directories and files that you can download. You will also find html files that display a graphical interface to the directories. When you click a file that is intended to be downloaded, Mozilla or Netscape opens a window asking you where to put the file on your system. Refer to "Installing and Removing Software" on page 926 for information about unpacking and installing the software that you download.

TIP: When a File is Downloaded to Your Screen (and You See Garbage)

If garbage appears on your screen, the file is being downloaded to your screen. Click Stop and then Back: You should be back where you started. This time hold the SHIFT key down while you click the file you want: This tells Mozilla/Netscape to download the file instead of trying to display it.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020