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As recently as 1993, Internet services were accessible primarily through character-based interfaces using a variety of complex command sets. Best-selling books on the Internet contained page after page of screen displays or command sequences captured from UNIX-based systems executing basic Internet functions. By 1997, the World Wide Web came to dominate the popular view of the Internet as being a multimedia extravaganza.
Before the Web, the Internet services of interest to most people consisted of four basic functions. These were electronic mail (e-mail), Internet news, file transfer between computers (FTP), and remote login to another computer (telnet). Gopher was developed as an access system to make it easier to browse the Internet and to search for relevant information in a user-friendly manner. The invention of the World Wide Web quickly displaced Gopher as an interface to Internet services. Yet e-mail, FTP, news, and telnet remain important functions for most people.
Affordable Internet software for Windows first became available in Spring 1993. Prior to that time, Windows users were dependent for Internet access on expensive, proprietary, commercial products in which each vendor's offerings were mutually incompatible with every other vendor's offerings. Publication of the Winsock applications programming interface (API) provided a way for individual client software (such as a telnet or FTP client) to be compatible with every vendor's networking products. As a result, beginning in 1993 there was a blossoming of freeware, shareware, and commercial Internet software for Windows.
The World Wide Web was developed by the high energy physics community to distribute technical papers and other forms of data. It is a system that enables users to find and retrieve information by navigating a system of hypertext documents. In a hypertext document, selecting a highlighted word or phrase causes a new document to be retrieved and displayed. Educators, businesses, and hobbyists now use the Web to distribute multimedia information to a world-wide audience. Those interested in using the Web for teaching or publishing may find it useful to read my paper "Teaching and Publishing in the World Wide Web." It is available in both a plain text version and a WWW hypertext version.
The World Wide Web is the ultimate toy for those addicted to changing what they are looking at rather than viewing what they are looking at. It is the next step in addiction for those who have grown bored with using their TV's remote control to constantly change channels.
Viewing a Web document with a Windows graphical client such as Microsoft's Internet Explorer or Netscape's Navigator is something of a cross between reading a magazine and watching television. Textual information is displayed with typographic fonts and color graphics. The static display of information is often supplemented by animated graphics and background music. Sound and video clips can be activated by clicking an icon embedded in the document. Clicking on a highlighted word or phrase in the document may cause the reader to skip to another part of the displayed document, or it may cause yet another document to be retrieved. The Web leads the reader to skip from one document to another, retrieving information from servers scattered around the world.
Electronic mail probably is still the most widely used Internet function. A commonly used configuration requires that a user have an account on a POP (Post Office Protocol) mail server. The e-mail client software accesses the server and downloads any incoming messages to the user's PC. Mail composed at the user's PC is transmitted to the server, from where it is sent to its ultimate destination anywhere in the world.
Internet news, also referred to as USENET news, is a conferencing system made up of tens of thousands of topical conferences known as news groups. Those familiar with the electronic bulletin board systems of the 1980's and early 1990's will compare Internet news to echo conferences. Others will draw an analogy to mailing lists such as listserv on BITNET. The user reads the news by using client software to subscribe to a selection of news groups. When the client software accesses an NNTP (Network News Transfer Protocol) server, the server downloads to the client a list of subjects for all unread messages stored on the server for the selected news group. The user can then select any message for reading, post a response to the message to the group, or reply directly to the original poster of the message. The client software maintains on the user's PC a list of all available groups on the server, along with records of which messages have been read or skipped over. Only the messages selected for reading are actually downloaded to the user's PC.
FTP (File Transfer Protocol) allows the transfer of files between any two computers of any type. Files can be transferred from PC to PC, PC to mainframe, PC to Mac, PC to UNIX machine, and vice versa. Any kind of computer file, whether it be a text file or a binary file representing software, graphics images, or sounds, can be transferred. Of course, whether the file is usable on the receiving machine depends on the nature of the file and the availability of software to make use of the file.
Telnet enables the user of a PC to login to a host computer at another site on the Internet. The user's PC then acts as a dumb terminal attached to the remote host. Such access usually requires that the user have an account on the remote host. For instance, a student or faculty member at one university might have an account on a computer located at another university. Many commercial database services that require only a character-based interface are available via telnet, including services such as the Dow Jones News Service and the Lexis/Nexis service. Some services are available without charge. For example, hundreds of libraries in all parts of the world allow free remote access to their computerized catalogs and to some specialized databases.
Gopher was an early system that enabled the user to find files and other Internet services by navigating a system of text menus and submenus. As a corollary, it provided a means for information providers to publish information on the Internet in a discoverable manner. Prior to the development of Gopher at the University of Minnesota in the early 1990's, information on the Internet was located by asking friends and strangers where to look. Gopher was rendered obsolete by the greater capabilities of the World Wide Web. Despite Gopher's obsolescence, in May 2000 a search on Yahoo for the phrase "gopher server" returned more than 24,000 web pages, including some links to Gopher servers that were still functioning.
The first step in using a Gopher client was to "point" the client at the address of a known Gopher server. The client then retrieved that Gopher's menu of topics. Typically, many of the topics on a Gopher menu were pointers to yet other menu items on other Gopher servers. The fact that each item in the sequence of selections might have come from different Gopher servers in widely scattered parts of the world was transparent to the user. The Gopher client software presented the many different Gopher servers as if they represented a single application on a single machine. Navigating such menus could lead the user to skip from one Gopher server to another, literally retrieving information from servers scattered around the world in just a few minutes.
Items on Gopher menus could be of many different data types in addition to menus listing choices of topics. When an item such as a text, graphics, or sound file was selected, the Gopher client transfered the file to the user's PC. Then, as an option, it might load the file into an appropriate "viewer" selected by the user. A simple text file could be loaded into Windows Notepad. A graphics file in GIF or JPEG format might be loaded into LVIEW, a popular shareware graphics viewer for Windows. A binary program file would simply be downloaded into a designated directory for use at some other time. Finding relevant Gopher menu items was facilitated through the use of Veronica, which was a database of the text of Gopher menus. Most Gopher servers included Veronica access as a menu selection.
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Revised: May 12, 2000
Harry_M_Kriz , [hmkriz@vt.edu]