Return to course introduction.
The World-Wide Web (WWW) is an attempt to present all the information on the internet as a seamless hypertext document. Hypertext can be thought of as a 3-dimensional view of information. Whereas information on the printed page is presented in 2 dimensions, hypertext allows a third dimension; selected words in a hypertext document represent a link to additional related information. Links can be expanded and replaced by another document at will.
These on-line notes are an example of a hypertext document. As you have seen, you can expand links to get more detailed information on a subject, see a biography of someone (including a picture), or even hear a person's voice.
There is an on-line summary of what WWW is about available from CERN. The CERN group has also produced a WWW Library indexed by subject.
There are many different interfaces available for accessing and traversing the Web. Netscape is one of the more popular interfaces. Netscape is a hypermedia browser that makes it easy to find and display information from all over the internet. Originally prototyed as Mosaic at the National Center for Supercomputing Applications (NCSA) at the University of Illinois, it is now widely available, as a commercial product.
Netscape is available on the Macintosh computers in CLARC and in Taylor Hall 41B. To find the class notes, you first must run netscape (which you'll find in the desktop folder). The default page will come up (which could be a page at Netscape corporation or perhaps a local page designed by the Computer Center), and then you must open the class notes. To do that, you must know the URL.
In order to retrieve information on the internet, Netscape must know its address. Netscape uses Uniform Resource Locators (URLs) as an addressing mechanism. URLs combine the address of the resource and the format of the resource within a single name (or address). A URL includes the name of the machine that holds the file, the pathname of the file, and the name of the protocol to be used to retrieve the data.
In general, if you know the URL of a resource, you can retrieve it using Netscape, or include it in a document of your own creation. One of the options available on the file menu is "Open URL" which allows you to open any document for which you have the URL.
The URL for the class notes is http://www.cs.rochester.edu/users/faculty/leblanc/csc173.
Netscape's easy-to-use point and click interface offers several options for navigating among documents. Netscape maintains a history of documents that have been displayed, and offers several commands for moving among documents in the history.
There is a tremendous amount of information available on the internet via the World-Wide Web. In the unlikely event you have never explored this resource, the search icon in Nescape gives you access to a number of global web indices compiled by web-crawling software robots, which will provide pointers to pages containing key subject words or combinations thereof, and sometimes more complicated concepts. That's one starting point. There are many others.