HTML and CSS Reference
In-Depth Information
Chapter 1
Introduction to HTML5
WebSocket
This topic is for anyone who wants to learn how to build real-time web applications.
You might say to yourself, “I already do that!” or ask “What does that really mean?” Let's
clarify: this topic will show you how to build
truly
real-time web applications using a
revolutionary new and widely supported open industry standard technology called
WebSocket, which enables full-duplex, bidirectional communication between your client
application and remote servers over the Web—without plugins!
Still confused? So were we a few years ago, before we started working with HTML5
WebSocket. In this guide, we'll explain what you need to know about WebSocket, and
why you should be thinking about using WebSocket today. We will show you how to
implement a WebSocket client in your web application, create your own WebSocket
server, use WebSocket with higher-level protocols like XMPP and STOMP, secure traffic
between your client and server, and deploy your WebSocket-based applications. Finally,
we will explain why you should be thinking about using WebSocket right now.
What is HTML5?
First, let's examine the “HTML5” part of “HTML5 WebSocket.” If you're already an expert
with HTML5, having read, say,
Pro HTML5 Programming
, and are already developing
wonderfully modern and responsive web applications, then feel free to skip this section
and read on. But, if you're new to HTML5, here's a quick introduction.
HTML was originally designed for static, text-based document sharing on the
Internet. Over time, as web users and designers wanted more interactivity in their HTML
documents, they began enhancing these documents, by adding form functionality and
early “portal” type capabilities. Now, these static document collections, or web sites,
are more like web
applications
, based on the principles of rich client/server desktop
applications. These web applications are being used on almost any device: laptops, smart
phones, tablets—the gamut.
HTML5 is designed to make the development of these rich web applications easier,
more natural, and more logical, where developers can design and build once, and deploy
anywhere. HTML5 makes web applications more usable, as well, as it removes the need
for plugins. With HTML5, you now use semantic markup language like
<header>
instead
of
<div class="header">.
Multimedia is also much easier to code, by using tags like
