Making sense of HTML5 - Build Windows 8 Apps with HTML5 and JavaScript - page 23

Chapter 2

Making sense of HTML5

Broadly speaking, the short words are the best, and the old words best of all.
—Winston Churchill
HTML5 is the latest version of the HTML language—the popular text-based language used

to define the content of webpages. HTML appeared on the scene in the early 1990s. In the
beginning it was merely a markup language apt at describing simple documents. A markup language
is a language based on a set of markers that wrap text and give it a special meaning.

Initially, the set of HTML markup elements, called “tags” or (better) “elements,” was fairly limited.
It contained elements to define references to other documents and headings, to link to images
and paragraphs, and apply basic text styling such as bold or italic. Over the years, however, the
role of HTML grew beyond imagination, progressing from being a simple language that described
documents to a language used to define the user interface of web applications. That trend continues
today with HTML5.

The latest version of HTML5 removes some of the older elements and makes it easier to keep
elements that provide style information in one place, and elements that provide text and define the
layout of the text, in another place. As you'll see in more detail in the next chapter, style information
can be defined through a special distinct file known as a Cascading Style Sheet (CSS). In addition,
HTML5 adds some new elements suitable for including multimedia content and drawing, and several
new frameworks for manipulating the content of the page programmatically.

With HTML5 alone, you still won't be able to go too far toward building a complete application.
However, the union of HTML5, CSS, and JavaScript functions as a close approximation to a full
programming language.

You use HTML5 to define the layout of the user interface and to insert text and multimedia.

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You use CSS to add colors, style, and shiny finishes.

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Finally, you use JavaScript to add behavior by gluing together pieces of native frameworks
such as Document Object Model (DOM), local storage, geolocation and, for example, all the
specific services of Windows 8 exposed via the Windows 8 JavaScript library (WinJs). The DOM,

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