Stylesheets and JavaScript
Browsers also have support for two powerful innovations to HTML: stylesheets and JavaScript. Like their desktop publishing cousins, stylesheets let you control how your web pages look—text font styles and sizes, colors, backgrounds, alignments, and so on. More important, stylesheets give you a way to impose display characteristics uniformly over the entire document and over an entire collection of documents.
JavaScript is a programming language with functions and commands that let you control how the browser behaves for the user. Now, this is not a JavaScript programming book, but we do cover the language in fair detail in later chapters to show you how to embed JavaScript programs into your documents and achieve some very powerful and fun effects.
The W3C—the putative standards organization—prefers that you use the CSS model for HTML/XHTML document design. All modern GUI browsers support CSS and JavaScript. The ancient Netscape 4 alone also supports a JavaScript Style Sheet (JSS) model, which we describe in Chapter 12, but we do not recommend that you use it. Let’s rephrase that—don’t waste your time on JSS. CSS is the universally approved, universally supported way to control how your documents might (not will) usually be displayed on users’ browsers.
To illustrate CSS, here’s a way to make all the top-level
(h1) header text in your HTML
document appear in the color red:
<html> <head> <title>CSS Example</title> <!— Hide CSS properties within comments ...
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