Your computer is a “Web Client” when you use
it to connect to the Internet. A “Web Browser” is the
software used to make your computer a web client. A computer connected to the Internet and
contains files made publicly available through the Internet are called “Web Servers”.
A browser allows many different types of Operating Systems
(OS) access a public file. Examples of OS's are Windows 95, 98, NT, UNIX, Macintosh, DOS,
OS/2, and SUN to name a few. Each of these systems can access the same Hypertext Markup
Language (html) file by using a browser such as Netscape Navigator or IE.
Public files on Web servers are ordinary text files. A web browser can read ordinary text. HTML is the standard text used on the Web.
What is HTML?
Short for HyperText Markup
Language, the authoring language used to create documents on the World Wide Web. HTML
is similar to SGML, although
it is not a strict subset. It is currently the standard used on the Web. HTML uses
codes, or tags, to tell the browser software how to display the text contained in the
document.
For example the following code: <U>Designing
</U><I>web pages can be <B>fun</B> </I> once you
<B>know</B> a few tricks.
Looks like this: Designing web pages can be fun
once you know a few tricks.
HTML provides a variety of text formatting tags that you can use to indicate headings, paragraphs, bulleted lists, numbered lists, and other useful text formats in an HTML document.
The real power in HTML lies in the anchor tag. The anchor tag enables you to link multiple HTML documents to each other. When an anchor tag is used to link to another document, you create a hypertext link, otherwise known as a hyperlink or link. Most web browsers display hyperlinks in a different color and are usely underlined
When a web browser displays an HTML document, the is generally referred to as a Web Page.
Hyperlinks general link to other HTML documents, however a link can connect to images, sound clips, and video clips. These type of links are generally referred to has as a hypermedia links.
A web site is a collection of linked Web pages that has a common theme or focus. The main page that all of the pages on a particular web site are organized around and link back to is called the site's home page.
A home page is used at least three different ways on the web and that it is sometimes difficult to tell which meaning people intend when they use the term. The first meaning indicates the main page for a particular site: this home page is the first page that opens when you visit a particular Web site.
The second definition of a home page is the first page that opens when you start your browser.
The third definition of a home page is the Web page that a particular Web browser loads the first time you use it.
Home pages that fall in the second and third definitions are often referred to as "start pages".
There is no centralized control over the Internet. Therefore no central starting point exists for the Web. However each computer on the Internet does have a unique identification number called an IP address. IP addressing currently uses a 4-part number. There are a possiblity of 4.2 billion possible addresses.
Or DNS (Domain Name Server). DNS maps a domain name to an IP address. Try this at a command prompt... c:\>ping www.microsoft.com see what the IP address is. Then take the IP address and use this c:\>ping -a 207.46.130.150 and see the hostname. Are they the same.
In this case the domain name is www.microsoft.com and the IP address is 207.46.130.150
Domain names follow a hierarchical model that you can follow from top to bottom if you read the name from right to left. (ie) the name gsb.uchicago.edu is the computer connected to the Internet at the Graduate School of Business (gsb) which is an academic unit of the University of Chicago (uchicago), which is an educational institution (edu). No other computer on the Internet has the same domain name.
The last part of a domain name is called its top-level domain. DNS software on the Internet host computer that is responsible for the edu domain keeps track of the IP address for all of the educational institutions in its domain, including uchicago. Similar DNS software on the uchicago Internet host computer keeps track of the academic units' computers in its domain, including gsb computer.
Currently there are 7 top-level domain names used. (.com, .edu, .gov, .int, .mil, .net, .org)
In addition to the top-level domain names, Internet comupters outside the US often use two-letter country domain names. (ie) uq.edu.au is the domain name for the University of Queensland (uq), educational institution (edu) in Australia (au).
See pages 3.6 - 3.7 for a more in-depth review of this.
The ip address and the domain name each identify a particular computer on the Internet, but do not indicate where a Web page's HTML document resides on that computer. To identify a web page's exact location, Web browsers rely on URLs. A URL is a four part addressing scheme that tells the web browser:
The transfer protocol can be http:// ftp:// telnet://
The pathname describes the hierarchical directory or folder structure on the computer that stores the file. URLs use the / (forward slash) like UNIX to separate the structure levels.
Not all URLs include a filename. If a URL does not include a filename, most Web browsers will load the file named index.html. The index.html filename is the default name for a web site's home page.