HTML Introduction


In this first section, we'll be looking at

  1. Client-Server Architecture
  2. Uniform Resource Locators
  3. Hypertext Markup Language
  4. HTML Tags



What is Client-Server Architecture?

The WWW protocols follow the client-server model of computing. When surfing the web, the following process occurs:
  1. Client software (the web browser running on your desktop computer) connects to a web server, and requests a copy of a file that resides on that server.
  2. The Server then performs several tasks:
    1. acknowledges the client's attempt to connect
    2. sends a copy of the requested file (whether it's an HTML document, image, sound, etc.)
    3. breaks the connection to the client
  3. The Client software receives and displays the file on the user's desktop. There is no longer any connection whatsoever to the web server.

Since the processing is split between the client software and the server software, both computers' resources can be more efficiently utilized. It also means that the user won't see any changes that are made to a file while they are viewing it. The user would have to "Reload" the file, i.e., request a current copy of the file from the web server.

What are URLs?

Uniform Resource Locators are the unique addresses or locations of resources on the Internet. When you hear 'URL,' think 'street address': just like the pizza delivery driver needs to know your address to deliver your pizza, your browser needs to know the URL of the web site to get there. A URL consists of "pathnames" to files located on computers throughout the world. URLs consist of three parts which are all CASE SENSITIVE:
  1. the protocol to be used to identify the retrieval method (in this case the HyperText Transfer Protocol):
    http://
  2. an address identifying the machine on which the file resides:
    skyways.lib.ks.us
  3. the path to the directory where the item is located on that machine, and the file's name.
    /kansas/training

The full URL looks like this : http://skyways.lib.ks.us/kansas/training/intro_html.html

What is HTML?

HTML is short for Hypertext Markup Language. It's not programming, but a method of assigning "tags" to text and images so they'll display in a web document.

HTML is based on SGML (Standard Generalized Markup Language), which is used to describe the general structure of various kinds of documents, and is being used in the creation of digital libraries. Browsers (such as Netscape), or to use the lingo, clients, take the formatting tags in an HTML document and arranges it into what you see when a web page is loaded.

Different browsers will format the same HTML tags in different ways, and users can change preferences in their browsers that affect the way web pages look. For this reason, web page design must be well structured and adhere to HTML standardization.

What Are Tags?

Tags are the tools used to create an HTML document and to format text for an internet browser. There are "beginning" and "ending" tags (covered here) and "empty tags."

Tag Descriptions


Beginning and Ending Tags

The purpose of beginning and ending tags is to begin and end changes to a web document and to text and graphics that appear on the page. If you begin an effect (such as making text bold), you have to turn it off at some point. Ending tags are typically the same as the beginning tags except they contain a frontslash (/). For example, the heading that proceeds this paragraph is tagged as follows:

<STRONG>Beginning and Ending Tags</STRONG>

The <STRONG> tag assigns a bold text attribute which is ended by the </STRONG> tag.

<HTML></HTML>

The <HTML> tag appears at the top of your HTML document as the first tag. This tag tells a web browser to display an HTML document. The <HTML> tag ends with </HTML> as the last tag in an HTML document.

<HEAD></HEAD>

The <HEAD> tag appears directly after <HTML> and encloses the document title. Within Pulse (see "Unique Pulse HTML Requirements" below) it also encloses information about the document Author, Contact Person, Department, Expiration Date and Keyword information. The <HEAD> tag ends with </HEAD>.

<TITLE></TITLE>

The <TITLE> tag appears between the <HEAD></HEAD> tags and contains a document title that you assign and which appears in the browser title bar. The <TITLE> tag ends with </TITLE>.

<BODY></BODY>

The main content of your document begins with the <BODY> tag and ends with the </BODY> tag. Information such as document background colors and background patterns can also be assigned within the </BODY> tag. The </BODY> tag appears next-to-last just prior to the </HTML> tag.

We've now reviewed the key "tags" that make up the "shell" of a web document. Now take a look at these tags in action:

ASSIGNMENT: Paste the following into WordPad to create a web document. Save the file to your disk and name it 'yourlastname.html'. Then open the file in Netscape. We will build on this same document throughout this tutorial.

<HTML>


	<HEAD>

		<TITLE>Library or Town Name</TITLE>

	</HEAD>

	<BODY>

		Replace this text with whatever you want. 

	</BODY>

</HTML>

Above: an HTML document "shell"


Move on to Section Two of the training



REVIEW
Introduction | Section Two | Section Three
Section Four | Design Considerations