| What is WWW? |
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(MCC National Newsletter: January 1994) WWW stands for the "World Wide Web" (also known as W3). The WWW project, started and driven by CERN (the European Laboratory for Particle Physics), seeks to build a distributed hypermedia system. To access the web, you run a browser program. The browser reads documents, and can fetch documents from other sources. Information providers set up hypermedia servers from which browsers can get documents. The browsers can, in addition, access files by ftp, nntp (the Internet news protocol), gopher and an ever-increasing range of other methods. On top of these, if the server has search capabilities, the browsers will permit searches of documents and databases. The documents which the browsers display are hypertext documents. Hypertext is text with pointers to other text. The browsers let you deal with the pointers in a transparent way -- select the pointer, and you are presented with the text that is pointed to. Hypermedia is a superset of hypertext -- it is any medium with pointers (URLs) to other media. This means that browsers might not display a text file, but might display images or play sound or animations. What is a URL?URL stands for "Uniform Resource Locator". It is a draft standard for specifying an object on the Internet, such as a file or newsgroup. URLs look like this: http://www.mcc.ac.uk/newsletters/National/9309/images/vpx240.jpg The first part of the URL, before the colon, specifies the access method. The part of the URL after the colon is interpreted specific to the access method. In general, two slashes after the colon indicate a machine name (machine:port is also valid). How can I access the web?You have two options:
How does WWW compare with GOPHER and WAIS?While all three of these information presentation systems are client-server based, they differ in terms of their model of data. In gopher, data is either a menu, a document, an index, or a Telnet connection. In WAIS, everything is an index and everything which is returned from the index is a document. In WWW, everything is a (possibly) hypertext document which may be searchable. In practice, this means that WWW can represent the gopher (a menu is a list of links, a gopher document is a hypertext document without links, searches are the same, Telnet sessions are the same) and WAIS (a WAIS index is a searchable page, returning a document with no links) data models as well as providing extra functionality. The principal difference between the three systems, it turns out, is deployment. WWW does not have as large a user base as gopher, mainly because of the small number of WWW browsers available. This is changing as WWW reaches critical mass (usage of the server at CERN doubles every 4 months -- twice the rate of Internet expansion). Some of the documents available:This list was taken from one of the WWW documents, entitled Starting Points for Internet Exploration, and can be found on the Mosaic and WinMosaic drop-down menus.
The experimental WWW server at MCC has all the National Service Newsletters for 1993, including the photographs as JPEG Images. A link from the MCC server goes to the SuperJANET WWW server at the Rutherford Appleton Laboratory, which gives details of SuperJANET projects and an on-line copy of Network News. How do I get my Information onto the WWW?The text documents on the WWW are stored in HTML (Hyper-Text Markup Language) format in normal ascii files, but there are packages which will convert RTF (Rich Text Format) to HTML. If you have some documents which are relevant to the National Supercomputer or Datasets Service, and you would like to make them available on the WWW, then please let me know. P.S
John Heaton MCC Network Unit |