by Mark R. Brown
Contrary to what the media would have you believe, the World Wide Web did not spring into being overnight. Though relatively new in human terms, the Web has a venerable genealogy for a computing technology. It can trace its roots back over 35 years, which is more than half the distance back to the primordial dawn of the electronic computing age.
The World Wide Web is actually just one of many applications that run on the Internet, a worldwide network of computer networks (or internetwork) that has been around in one form or another since 1961.
ON THE WEB: If you're curious about the origins of the Internet, read Bruce Sterling's excellent article on the subject at gopher://oak.zilker.net:70/00/bruces/F_SF_Science_Column/F_SF_Five_.
By the mid-1970s, many government agencies, research facilities, and universities were on this internetwork (which was then called ARPAnet), but each was running on its own internal network developed by the lowest bidder for their specific project. For example, the Army's system was built by DEC, the Air Force's by IBM, and the Navy's by Unisys. All were capable networks, but all spoke different languages. What was clearly needed to make things work smoothly was a set of networking protocols that would tie together disparate networks and enable them to communicate with each other.
In 1974, Vint Cerf and Bob Kahn published a paper titled "A Protocol for Packet Network Internetworking" that detailed a design that would solve the problem. In 1982, this solution was implemented as TCP/IP. TCP stands for Transmission Control Protocol; IP is the abbreviation for Internet Protocol. With the advent of TCP/IP, the word Internet--which is a portmanteau word for interconnected networks--entered the language.
The Department of Defense quickly declared the TCP/IP suite the standard protocol for internetworking military computers. TCP/IP has been ported to most computer systems, including personal computers, and has become the new standard in internetworking. It is the TCP/IP protocol set that provides the infrastructure for the Internet today.
TCP/IP comprises over 100 different protocols. It includes services for remote logon, file transfers, and data indexing and retrieval, among others.
ON THE WEB: An excellent source of additional information on TCP/IP is the introduction to the TCP/IP Gopher site at the University of California at Davis. Check it out at gopher://gopher-chem.ucdavis.edu/11/Index/Internet_aw/Intro_the_Internet/intro.to.ip/.
ON THE WEB: http://www.eff.org/papers/bdgtti/eegtti.html One of the best online guides to the Internet as a whole is the Electronic Freedom Foundation's Extended Guide to the Internet.
There were a plethora of different data-indexing and retrieval experiments in the early days of the Net, but none was all-pervasive until, in 1991, Paul Lindner and Mark P. McCahill at the University of Minnesota created Gopher. Though it suffered from an overly cute (but highly descriptive) name, its technique for organizing files under an intuitive menuing system won it instant acceptance on the Net. The direct precursor in both concept and function to the World Wide Web, Gopher lacked hypertext links or graphic elements (see Figure 1.1). Although Gopher servers sprung up quickly all over the Internet, it was almost immediately apparent that something more was needed.
FIG. 1.1
Most Web browsers, like Netscape Navigator, can also display information on Gopher
sites like this.
By the time "Gopherspace" began to establish itself on the Net, the European High-Energy Particle Physics Lab (CERN) had become the largest Internet site in Europe and was the driving force in getting the rest of Europe connected to the Net. To help promote and facilitate the concept of distributed computing via the Internet, Tim Berners-Lee created the World Wide Web in 1992.
The Web was an extension of the Gopher idea, but with many, many improvements. Inspired by Ted Nelson's work on Xanadu and the hypertext concept, the World Wide Web incorporated graphics, typographic text styles, and--most importantly--hypertext links.
NOTE: The hypertext concept predates personal computers. It was first proposed by computer visionary Ted Nelson in his ground-breaking, self-published book Computer Lib/Dream Machines in 1974.
In a nutshell, electronic hypertext involves adding links to words or phrases. When selected, these links jump you to associated text in the same document or in another document altogether. For example, you could click an unfamiliar term and jump to a definition, or add your own notes that would be optionally displayed when you or someone else selected the note's hyperlink.
The hypertext concept has since been expanded to incorporate the idea of hypermedia, in which links can also be added to and from graphics, video, and audio clips.
The World Wide Web used three new technologies:
Using HTML, almost anyone with a text editor and access to an Internet site can build visually interesting pages that organize and present information in a way seldom seen in other online venues. In fact, Web sites are said to be composed of pages because the information on them looks more like magazine pages than traditional computer screens.
NOTE: HTML is, itself, an outgrowth of the much more complex SGML, or Standard Generalized Markup Language. SGML is (rarely) also used for creating pages on the Web, though it takes a different browser to be able to view SGML pages. You can find out all about SGML at http://www.w3.org/pub/WWW/MarkUp/SGML/.
HTML is a markup language, which means that Web pages can only be viewed by using a specialized Internet terminal program called a Web browser. In the beginning, the potential was there for the typical computing "chicken and the egg problem": no one would create Web pages because no one owned a browser program to view them with, and no one would get a browser program because there were no Web pages to view.
Fortunately, this did not happen, because shortly after the Web was invented, a killer browser program was released to the Internet community--free of charge!
In 1993, the National Center for Supercomputing Applications (NCSA) at the University of Illinois at Champaign-Urbana released Mosaic, a Web browser designed by Marc Andreessen and developed by a team of students and staff at the University of Illinois (see Figure 1.2). It spread like wildfire though the Internet community; within a year, an estimated two million users were on the Web with Mosaic. Suddenly, everyone was browsing the Web, and everyone else was creating Web pages. Nothing in the history of computing had grown so fast.
ON THE WEB: http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/ For more information on NCSA Mosaic, check out the NCSA Web site.
FIG. 1.2
NCSA Mosaic, the browser that drove the phenomenal growth of the World Wide Web.
By mid-1993, there were 130 sites on the World Wide Web. Six months later, there were over 600. Today, there may be as many as a million Web sites in the world (depending on whose figures you believe).
Mosaic's success--and the fact that its source code was distributed for free--spawned a wave of new browser introductions. Each topped the previous by adding new HTML commands and features. Marc Andreessen moved on from NCSA and joined with Jim Clark of Silicon Graphics to found Netscape Communications Corporation. They took along most of the NCSA Mosaic development team, which quickly turned out the first version of Netscape Navigator for Windows, Macintosh, and UNIX platforms. Because of its many new features and free trial preview offer, Netscape Navigator quickly became the most popular browser on the Web. The Web's incredible growth even attracted Microsoft's attention, and in 1995, they introduced their Internet Explorer Web browser to coincide with the launch of their new WWW service, the Microsoft Network (MSN).
Established online services like CompuServe, America Online, and Prodigy scrambled to meet their users' demands to add Web access to their systems. Most of them quickly developed their own versions of Mosaic, customized to work in conjunction with their proprietary online services. This enabled millions of established commercial service subscribers to spill over onto the Web virtually overnight; "old-timers" who had been on the Web since its beginning (only a year and a half or so before) suddenly found themselves overtaken by a tidal wave of Web-surfing newbies. Even television discovered the Web, and it seemed that every other news report featured a story about surfing the Net.
The World Wide Web didn't get its name by accident. It truly is a web that encompasses just about every topic in the world. A quick look at the premier index to the Web, Yahoo! (http://www.yahoo.com), lists topics as diverse as art, world news, sports, business, libraries, classified advertising, education, TV, science, fitness, and politics (see Figure 1.3). You can't get much more diverse than that! There are literally thousands of sites listed on Yahoo! and other online indexes.
FIG. 1.3
If you really want to know what's on the Web, you need look no further than Yahoo!,
which serves as a good example of an excellent Web site itself.
ON THE WEB: http://www.boutell.com/faq For more information about the World Wide Web, consult the WWW FAQ.
The World Wide Web explosion shows no signs of slowing down. It proved so intuitive and so much fun to use that people almost immediately began to see other uses for the Web browsing "metaphor."
One of the first and most obvious was to build Webs that didn't communicate over the Internet at all, but were confined within the computer systems of individual companies and institutions. A term was quickly coined to distinguish these internal Webs: intranets.
The major difference between an intranet and a Web site--besides the obvious fact that the former is constrained to an individual site, while the latter is worldwide--is the audience. On a Web site, the content is aimed at the public, while an intranet addresses the needs of an organization's own employees (see Figure 1.4).
FIG. 1.4
HTML-based corporate intranets like this one give employees quick-and-easy access
to company databases and resources.
This means that intranets are more likely to contain company-specific--even confidential--data, such as sales reports, customer databases, training materials, and employee manuals.
Though these kinds of data have been available on internal corporate networks for years, the difference with intranets is in the presentation. HTML and associated technologies are used to create user interfaces which are as fun and easy to use as those on most World Wide Web sites. Data which might have previously been locked up in difficult-to-use corporate databases can be made easily accessible to even computer novices.
Even with only a year or two of real-world usage, the utility of corporate intranets has already been proved beyond the shadow of a doubt. Netscape Communications Corporation, a publisher of Web-server and client software and one of the premier advocates of intranet development, says that a resounding majority of their intranet customers report substantial cost savings after installing corporate intranets. Some have claimed 1000% returns on their investments, according to Netscape. In the world of business, this is a phenomenal rate of return, and a claim which has grabbed the attention of the majority of Fortune 500 companies--as well as many that are much, much smaller.
ON THE WEB: http://home.netscape.com/comprod/announce/roi.html Use this site to read Netscape Communication Corporation's study on intranet return-on-investment.
In fact, interest in intranets is so great that HTML server and client publishers like Netscape and Microsoft predict that the majority of their HTML-related income over the next few years will be generated by intranet development, not the World Wide Web.
HTML is also showing up in many other places you might not expect--electronic mail, for example.
E-mail was one of the first Internet applications. It changed the way scientists collaborated in the mid-60s, and continues to be one of the major applications of Internet technology. Millions more people use the Internet for e-mail than use it for Web surfing.
Perhaps, then, it should come as no surprise that HTML has made its way into e-mail messages. HTML affords the same benefits to e-mail as it does to Web pages or intranets: an easy and fun-to-use interface; integration of text and graphics; hyperlinks; and the ability to integrate video, sound, and applications inline, to name just a few.
Where e-mail is just a way to exchange text, HTML-enhanced e-mail can enhance and reinforce text messages with graphics or other "rich" information. After all, sometimes a picture--or sound bite, or video clip--is worth a thousand words, or more.
Hyperlinks mean the ability to link an e-mail message to Web sites or intranet information. Integrated applications mean the ability to include even "live" spreadsheets or other data into e-mail messages.
Extend this concept to newsgroups (see Figure 1.5), and you have the ability to turn static, all-text news postings into truly collaborative works. One worker can post an HTML message which contains an AutoCAD drawing, for example, and all the other members of the group can comment on it, adding notes or even making changes to the drawing itself.
FIG. 1.5
E-mail messages and newsgroup postings created with HTML can have all the look, feel,
and functionality of Web pages.Clearly, HTML in messages--both e-mail and newsgroups--may
have as much of an impact on the way people communicate and collaborate online as
the Web or intranets have already had.
CAUTION: Not all e-mail programs and newsgroup readers can correctly interpret HTML-enhanced messages. Only use HTML in such messages when you're sure your intended audience can read them properly.
But that's not the end of HTML's potential. Both Microsoft and Netscape are advocating that HTML be used as the basis for creating stand-alone applications, too.
That HTML's user interface is friendly and easy-to-use has certainly been well-established on the Web and corporate intranets. But, because HTML documents can also incorporate active objects like ActiveX controls, Java applets, and JavaScript scripts, HTML pages can act as containers for applications. HTML tags can be used to format text, graphics, interactive buttons, forms, and other objects on-screen which interact with the user just as any other GUI (Graphical User Interface). Incorporated into the HTML page are objects such as an ActiveX control or a Java applet (see Figure 1.6).
FIG. 1.6
This JavaScript-based online calculator is just a simple example of using HTML to
create the user interface for an application program.
By using HTML as the GUI-development language, the developer gains a whole list of advantages:
Netscape is actively pushing Sun's Java as its development language of choice, while Microsoft would like to see developers using their ActiveX controls. But each supports the other and--most importantly--both advocate HTML as the GUI-development language.
As this concept catches on, you'll see more applications developed with HTML interfaces, and HTML will become important in its own right as a language for "gluing together" mini-application modules (or applets), no matter what language those applets have been written in. In time, it may be the majority of special-purpose software and shareware is written in this way, and even a percentage of commercial applications may be developed in this manner.
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