4a) Visible N@vigators, browsers, and invisible "N@vigators": DNS Servers
To re@ch a dom@in, a sp@ce, or a p@ge, situated in a Web server, you tr@vel through the user friendly  interface of a "visible n@vigator", or browser,

generaly with Internet Explorer, 95%, or Netscape Navigator (and Communicator), 4%.

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Furthermore, to tr@vel on the Internet of copper, glass, and plastic, that now covers the whole planet, you n@vigate, amongst other hardware,

 through Bridges and Routers,  and DNS servers that are invisible to you.

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DNS servers choose the fastest available road between your computer and the dom@in that you wish to @ccess,

with the help of the DNS protocol, or  Domain Name System.

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DNS servers form a network of their own and  know all domain names, DNS servers automatically translate a dom@in n@me  into its IP, a sequence of 4 numbers,

each of which is between 0 and 245...To whom belongs IP 17.112.152.32?

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4. "N@vigators": DNS Servers ~NEXT to 4b

4.b) DNS servers choose their traject according to available ro@ds : from Quebec, you re@ch the Web servers that host the dom@ins of GeoCities.com, in California,

by tr@velling through ±15 DNS servers.
You may see traces of that ro@d, by doing a TRACERT:

Under Windows, click Start, Programs, Commands, MS-DOS, then, in MS-DOS, write : tracert: www.google.com

How many DNS servers to get there ?

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Verify three @dresses of three dom@ins, one of which, in Quebec. How many  DNS servers to tr@vel there?

What are the IP #s of those three dom@ins?

5a) Dissection of a dom@in's URL @ddress, as http://www.google.com

http, hyper text transfer protocol, is one of the protocoles TCP/IP that computers speak together.

www means World Wide Web (that is the cyber sp@ce where @re all dom@ins).

When you tr@vel on the Web, neither http, nor www are compulsory, to re@ch a dom@in:

Just writing google.com will get you there, because, by default,

you use http to tr@vel onto the World Wide Web.

http://google.com will also get you there,
just as www.google.com.

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Disgression: Did you know the www2.google.com and the www3.google.com?

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5. Dom@ins ~NEXT to 5b

5b) Dissection of dom@in n@mes:

google is the second level domain (SLD)

com represents the extension,and is also called top level domain (TLD).

There are generic extensions with three letters or more, as     .com    .net    .org    .info

and geographical extensions with two letters, as .ca    .ch    .mx

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So, the SLD and TLD  google.com is a dom@in n@me;

that name is unique, and may only be used by one holder at the time, as djo.ca

A dom@in n@me may be written in capital letters or not: it is not case sensitive.

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Indicate the URL @ddress of four p@ges or Sp@ces that you often visit. Identify which part of the @ddress is the dom@in n@me.

Find out to whom belongs those dom@ins, with a research WHOIS.