Datasheet

When the formatting needs to change, the CSS document alone can be updated, and the changes are

then reflected in all documents that use that style sheet. The “cascade” in the name refers to the feature

that allows styles to be overridden by subsequent styles. For example, the HR department Web pages

for Acme Inc. can use the company style sheet but also use styles specific for the individual department.

The result is that all of the Acme Inc. Web pages look similar, but each department has a slightly unique

look and feel.

Note: CSS is covered in depth in Part II of this book.

HTML 4.01

Heralded as the last of the HTML standards, 4.01 fixed errors inherent in the 4.0 specification and made

the final leap to embracing CSS as the vehicle for document formatting (instead of using parameters in

HTML tags).

XHTML 1.0

Extensible Hypertext Markup Language is the latest standard for Web documents. This standard infuses

the HTML 4.01 standard with extensible language constructs courtesy of XML. It was designed to be

used in XML-compliant environments yet be compatible with standard HTML 4.01 user agents. As of

this writing, adoption of the XHTML standard for Web documents has been slow. Although most

browsers natively support HTML 4.01, most do not support the extensibility features of XHTML 1.0.

HTML Concept and Syntax

The concept and use of HTML is straightforward. Individual tags — special text strings that are inter-

preted as formatting commands by the browser — are placed within a document to lend structure and

format accordingly. Each tag has a beginning and an ending tag; everything between the tags is format-

ted according to the tag’s parameters or related style sheet.

HTML Tags

Each tag begins with a left-pointing angle bracket (<) and ends with a right-pointing angle bracket (>).

Between the brackets are keywords that indicate the type of tag. Beginning tags include any parameters

necessary for the tag; ending tags contain only the keyword prefixed by a slash.

For example, if you want a word to be bold in a document, you would surround it with bold tags (

<b>

and </b>) similar to the following:

If I wanted this word to be <b>bold</b> I would use bold tags.

Many tags require children tags to operate. For example, the <table> tag itself only marks the position

in the document where a table will appear; it does nothing to format the table into rows and columns.

Several child tags —

<tr> for rows, <td> for cells/columns, and so on— are used between the begin-

ning and ending

<table> tags accordingly:

<tr>

</tr>

The Basics of HTML

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