1 Web Developer Foundations: Using XHTML Chapter 2 Key Concepts.

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Web Developer Foundations: Using XHTML

Chapter 2Key Concepts

Learning Outcomes

In this chapter, you will learn about: The development of HTML The transition from HTML to XHTML XHTML syntax, tags, and document type

definitions The anatomy of a web page Formatting the body of a web page Formatting the text on a web page Physical and logical style tags Special Characters

What is HTML?

The World Wide Web Consortium (http://w3c.org) sets the standards for HTML and its related languages.

The set of markup symbols or codes placed in a file intended for display on a Web browser page.

Each individual markup code is referred to as an element or tag. Each tag has a purpose.

Tags are enclosed in angle brackets, "<" and ">" symbols.

Most tags come in pairs; an opening tag and a closing tag.

What isXHTML?

The newest version of HTML is actually XHTML – eXtensible HyperText Markup Language.

XHTML uses the tags and attributes of HTML along with the syntax of XML (eXtensible Markup Language).

While many web pages and web authoring tools still use HTML, as a web developer you need to learn about XHTML – you will be seeing a lot of it in the future.

What’s wrongwith HTML?

The Web has changed from a medium used to display electronic versions of paper documents to a medium that provides diverse information for a variety of devices.

HTML does not fit this need. HTML is a structural language – it was originally

intended to markup printed documents for online viewing.

With the expansion of the Web to include devices other than personal computers, the need for a descriptive rather than structural language became evident and XHTML was created.

XHTML was developed by the W3C to be the reformulation of HTML as an application of XML.

XHTML combines the formatting strengths of HTML and the data structure and extensibility strengths of XML.

XML An XML document must be well-formed.

Use lowercase Use opening and closing tags

<body> </body> Close stand-alone tag with special syntax

<hr /> XML documents begin with an XML directive.

The basic form of this directive is:<?xml version="1.0" encoding="UTF-8"?>

DocumentType Definition (DTD)

W3C Recommendation: Use a Document Type Definition to identify the type of markup language used in a web page.

XTML 1.0 TransitionalThis is the least strict specification for XHTML 1.0. It allows the use of both Cascading Style Sheets and traditional formatting instructions such as fonts. We will use this for most of our coding in this text

XHTML 1.0 StrictRequires exclusive use of Cascading Style Sheets. We will not use this.

XHTML 1.0 FramesetRequired for pages using XHTML frames. We will use this with our frames pages later in the text.

XHTML 1.0 Transitional DTD

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd>

First Web Page

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html> an opening tag

.... page info goes here

</html> a closing tag

Head & Body Sections Head Section -- Contains information that

describes the web page document. <head>…head section info goes here</head>

Body Section -- Used for text and tags that do show directly on the web page. <body>…body section info goes here</body>

XHTML<head> and <body> tags

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html> <head>

.... Header info goes here </head> <body> .... Body info goes here

</body></html>

XHTML<body> tag attributes

bgcolor Configures the background color of a web page

textConfigures the color of the text on the web page

Check the XHTML Reference in the Web Developers Handbook for more body tag attributes

XHTML<hx> tag attributes

Heading tag Adds a heading

<h1>Largest</h1> Largest<h2>next largest</h2> next largest

<h3>large</h3> large

<h4>small</h4> small

<h5>smaller</h5> smaller

<h6>smallest</h6> smallest

Check the XHTML Reference in the Web Developers Handbook for header tag attributes

XHTML<p> tag

Paragraph tag<p> …paragraph goes here </p>

Used to group sentences and sections of text together.

Text that is contained by <p> and </p> tags will have a blank line above and below it.

XHTML<br /> tag

Line Break tag Stand alone tag…text goes here<br />

This starts on a new line…. Used to force a new line when the text on

the web page document is displayed by a browser.

XHTMLDefinition List

Useful to display a list of terms and definitions or a list of FAQ and answers

<dl> tagContains the definition list

<dt> tagContains a defined term

<dd> tagContains a data definition

XHTMLDefinition List Example

<dd>Internet Protocol</dd>

<dd>Transmission Control

Protocol</dd>

XHTMLOrdered List

Used to convey information in an ordered fashion

<ol>Contains the ordered list type attribute determines numbering scheme

of list, default is numerals

<li>Contains an item in the list

XHTMLOrdered List Example

<li>Apply to school</li>

<li>Register for course</li>

<li>Pay tuition</li>

<li>Attend course</li>

XHTMLUnordered List

Used to display information in bullet points

<ul>Contains the unordered list type attribute determines the type of bullet

point, default is disc

<li>Contains an item in the list

XHTMLUnordered List Example

XHTML<pre> tag

Preformatted Text tag The preformatted text tag preserves your

formatting and displays the text in a fixed-width or monospace font.

…text goes here

Line breaks and formatting are preserved

</pre>

XHTML<blockquote> tag

Blockquote tag Used to indent a block of text for special

emphasis. <blockquote>

…text goes here

</blockquote>

XHTML<font> tag

Font tag Used to format text Deprecated – will be dropped in future versions of

XHTML Common attributes

face -- configure the typeface or font name to be used to display the text.

size – sets the size of the text color – configures the color of the textindent a block of

<font face=“Arial” size=“6” color=“#000099”>This is large blue text.</font>

XHTML<font> tag attributes

Font size:<font size="1">Size 1</font> Size 1

<font size="2">Size 2</font> Size 2

<font size="3">Size 3</font> Size 3

<font size="4">Size 4</font> Size 4<font size="5">Size 5</font> Size 5<font size="6">Size 6</font> Size 6<font size="7">Size 7</font> Size 7

Font face:<font face="Jokerman">Jokerman</font> Jokerman

XHTMLLogical Style Tags

Indicate the logical style used to display the text in between the container tags.

Common Logical Style Tags <strong></strong>

To cause text to be emphasized or to "stand out" from surrounding text. Usually displayed in bold. <strong>This is important</strong>

<em></em> To cause text to be emphasized in relation to other text

on the page. Usually displayed in italics.<em>Please note</em>

XHTMLPhysical Style Tags

provide specific font instructions for the browser Logical Style tags are preferred by the W3C Physical Style tags are discussed because some web

developers still use them Common Physical Style Tags <b></b>

To display as bold text <b>This is important</b>

<i></i> To display text in italics

<i>Please note</i>

XHTMLSpecial Characters

Used to display special characters such as quotes, copyright symbol, etc.

See the Special Characters section in the Web Developer’s Handbook for a detailed list(Page H-31)

Summary This chapter provided an introduction to

XHTML. It began with an introduction to the

HTML, discussed the transition to XHTML, continued with the anatomy of a web page, and introduced text and block-level formatting.

1 Web Developer Foundations: Using XHTML Chapter 2 Key Concepts.

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