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- MAP24: WWW (PART TWO)
- ---------------------
-
- "I love to sail forbidden seas, and land on barbarous coasts."
- -- Herman Melville, Moby-Dick
-
-
- Back to work.
-
- Yesterday I told you that "URLs" is pronounced "earls." In fact, a lot
- of people still use the initials and call them "U-R-Ls." I personally
- prefer calling them "earls" because "earls" rhymes with "squirrels,"
- but the choice of what you call them is completely up to you :)
-
- Let's take a look at how a sample WWW browser works. There are three
- basic types of WWW browsers available: line-mode browsers, full screen
- browsers (like Lynx), and graphical browsers (like Mosaic).
-
- Line-mode browsers are about as user un-friendly as you can get.
- This is hard to describe, but line-mode browsers work a little
- like FTP inasmuch as you type a command, get some information
- on your screen, type a new command, get some more information, and
- so on ...
-
- A full screen browser puts a menu on your screen that looks a little like
- the Gopher menus that we saw last week. You move the cursor up and down
- the screen, select a highlighted link, press enter or return, and you
- are automatically taken to a new document or file (your fill screen
- browser may work differently than this, though).
-
- Graphical browsers allow you to access not only text, but also pictures
- and sound (a.k.a. "hypermedia"). In fact, these pictures can be put in Web
- documents (a.k.a. Web pages), making that Web page look less like a
- Gopher menu and more like a page from a color magazine! Most graphical
- browsers use a mouse, and you point-and-click on a highlighted link to
- access it.
-
- The URL for the sample Web page that we are going to use today is
-
- http://ua1vm.ua.edu/~vmhttpd/index.html
-
- and I am going to be using the UF WWW Browser for CMS to access this
- page. I'll talk a little more about how you can access a WWW browser
- in a few minutes, but I first want to show you what a basic Web page
- looks like.
-
- The UF WWW Browser for CMS is the browser that my service provider
- uses, and it is a full screen browser. The browser that you use -- if
- you can even access a WWW browser -- will probably look and work a
- little differently than what you will see in this example.
-
- Finally, in real life my browser highlights the links by making them
- a different color than the rest of the text. There is no way for me to
- use different colors in this letter, so I have highlighted the links
- in this example by surrounding them with a (* *).
-
- Just like I can access an item in a Gopher menu by pointing at it and
- selecting it, I can access a WWW link by pointing at it and selecting
- it.
-
- Enough talk. Time for the example.
-
- I access my provider's WWW browser, and the following appears on my
- screen:
-
-
- Albert 1.2.0 (UF WWW Browser for CMS) Screen 1 of 2 (more screens)
- Viewing=http://ua1vm.ua.edu/~vmhttpd/index.html
- Title=UA1VM WWW Home Page
- Welcome to The University of Alabama's CMS WWW Server
-
- This CMS server is still under development. Any (*comments*)
- or (*suggestions*) will be greatly appreciated. Thank you.
-
- Gopher Sites:
- - (*UA1VM CMS Gopher Server*)
- - (*UA1IX AIX/370 Gopher Server*)
- - (*RISC/6000 Gopher Server*)
- - (*RICEVM1 CMS Gopher Server*)
- Telnet Sessions:
- - (*UA1VM.UA.EDU*)
- - (*UA1IX.UA.EDU - Line Mode*)
- - (*RISC.UA.EDU - Line Mode*)
- WWW Sites:
- - The University of Alabama Libraries (*WWW*)
- - The University of Illinois at Urbana-Champaign (*WWW*)
- - The Alabama Supercomputer Network (*WWW*)
- - NASA Information Services via (*WWW*)
- Leisure:
- - (*Intertext Magazine*) - Electronic Fictional Magazine at The
- University of Michigan
- - (*Wiretap*) - a gopher to Cupertino, California
- - (*NNR*) - UA1VM's Network News Reader
- Other Neat Stuff:
- - The University of Alabama Library's On-Line (*Card Catalog*)
- - a (*map*) of The University of Alabama campus
- ... snip snip snip ...
-
-
- COOL!
-
- I can select any of these links -- the words set apart from the rest
- of the text with a (* *) -- and be transported to that particular link.
- From this one Web page, I can access Gopher, telnet, and even other
- Web pages! (I can also access FTP, although this page does not show
- it).
-
- We've seen a lot of Gopher and telnet recently. Let's take a look at
- another Web page. Since I used to be a Simulations Director at the
- United States Space Camp (did I forget to tell you that?), I'm going
- to move my cursor down to the (*WWW*) link next to "NASA Information
- Services", press enter, and see what happens:
-
-
- Albert 1.2.0 (UF WWW Browser for CMS) Screen 1 of 2 (more screens)
- Viewing=http://hypatia.gsfc.nasa.gov/NASA_homepage.html
- Title=NASA Information Services via World Wide Web
- National Aeronautics and Space Administration
-
- NASA Logo
-
- (*World Wide Web (WWW) information services*)
-
- (*Hot Topics*) NASA news and subjects of public interest
- (*NASA Strategic Plan*)
- (*NASA Strategies, Policies, and Public Affairs*)
- (*NASA Online Educational Resources*)
- (*NASA Information Sources by Subject*)
- ... snip snip snip ...
-
-
- This is certainly more interesting than SURAnet! ;)
-
- From this Web page I can access OTHER Web pages, and from those Web pages
- I can access even MORE Web pages, and so on ...
-
- Yesterday I told you that it is possible for you to connect directly
- to a specific Internet resource so long as you know the resource's
- URL. *HOW* you do that depends on the browser that you use.
-
- For the line-mode browser at CERN, for example, the command to connect
- to a particular URL is
-
- GO <URL>
-
- replacing <URL> with the URL of the Internet resource that you want
- to access. In Lynx, you just select the "GO" link on the browser's
- start-up page; in most graphical browsers (like Mosaic), there is
- usually an "Open URL" option in one of the menus. (1)
-
- Before you can do this, however, you have to first access the Web.
- There are three ways that you can do this:
-
- 1. Through a browser stored on your local Internet service provider's
- machine. Ask your provider if your site has a Web browser, and how
- you can access it.
-
- 2. Through a browser stored on your own machine. Until recently,
- you had to have a SLIP or PPP connection to do this. Some
- providers -- providers who FLOODED my mailbox when I did
- not talk about the special Level 2.0002746278546723 access
- that they offer -- now allow you to store a Web browser on
- your own machine even though you only have Level 2 access.
-
- If you do not have a SLIP or PPP connection, contact your
- provider BEFORE you store a Web reader on your own computer
- and double-check that your provider will support the browser.
- *MOST* service providers can NOT support a Web browser unless
- you have a SLIP or PPP connection.
-
- 3. Through a telnet connection to a publicly-accessible Web
- browser.
-
- If you have a SLIP or a PPP connection, the WWW FAQ that I have stored on
- the University of Alabama's LISTSERV file server (WWW FAQ1) has a list
- of FTP sites where you can get specific Web browsers.
-
- (Do me a favor ... re-read that last sentence. Did you EVER think you
- would understand a sentence like that? Isn't this workshop COOL?!!)
-
- If you do not have access to a Web browser through your site, you may
- still be able to access a Web browser through telnet. The following are
- a couple of the public Web sites: (1)
-
- telnet address comments
- -------------- -----------------------
- info.cern.ch No password is required. This is in
- Switzerland, so U.S. users might be
- better off using a closer browser.
-
- www.cc.ukans.edu The "Lynx" full screen browser, which
- requires a vt100 terminal. Login as www.
- Does not allow users to "go" to arbitrary
- URLs.
-
- www.njit.edu Login as www. A full-screen browser at
- the New Jersey Institute of Technology.
-
- sun.uakom.cs Slovakia. Has a slow link, so only use
- from nearby.
-
- info.funet.fi Login as www. Offers several browsers,
- including Lynx (goto option disabled
- there too).
-
- fserv.kfki.hu Hungary. Has a slow link, so use from
- nearby. Login as www.
-
-
- Once you are on the Web, it is possible for you to do keyword searches
- (much like the Veronica searches we did last week) using one of the
- Web's many search engines. One of the best Web search engines is the
- WebCrawler. The WebCrawler's URL is
-
- http://www.biotech.washington.edu/WebQuery.html
-
- and the WebCrawler searches for documents whose title *AND CONTENT*
- match your keyword.
-
- Another Web search engine you probably will want to check out is
- the World Wide Web Worm. The Worm's URL is
-
- http://www.cs.colorado.edu/home/mcbryan/WWWW.html
-
- The Worm is not at thorough as the WebCrawler, but it is still a
- pretty competent search engine.
-
- Both of these search engines provide really good on-line help and instructions.
-
- One last thing, and I am though for today. Please remember:
-
- - The "Web" is the collection of all of the files and information
- that can be accessed by a Web browser.
-
- - Mosaic and Lynx and just BROWSERS that allow you to access the
- Web.
-
-
- SOURCES
-
- (1) WWW FAQ Part 1 - August 94, available from the University
- of Alabama's LISTSERV file server (GET WWW FAQ1 F=MAIL).
-
-
- PATRICK DOUGLAS CRISPEN THE VIEWS EXPRESSED IN THIS LETTER DO NOT
- PCRISPE1@UA1VM.UA.EDU NECESSARILY REPRESENT THE VIEWS OF THE
- THE UNIVERSITY OF ALABAMA UNIVERSITY OF ALABAMA - TUSCALOOSA
-
- ROADMAP: COPYRIGHT PATRICK CRISPEN 1994. ALL RIGHTS RESERVED.
-
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