The browser is, hands down, the most popular and ubiquitous deployment platform available to us today: virtually every computer, smartphone, tablet, and just about every other form factor imaginable can now execute JavaScript, render a web page, and of course, talk HTTP. This, on its own, is a remarkable achievement, especially when you realize that it only took us a little over a decade to get to this stage. However, this is also just the beginning. The browser of yesterday looks nothing like what we now have access to thanks to all of the innovations of HTML5.

It is hard to overstate the importance of what HTML5 WebSocket enables: up until

now, the browser could only speak one language (HTTP), and that language was not

designed for the requirements of the modern, real-time Web. Yes, we’ve made progress

with interim solutions such as long-polling and Flash sockets, but the complexity and cost

of these solutions has always limited the capabilities of what we could do. WebSockets

changes all of that: it is designed from the ground up to be data agnostic (binary and text),

full-duplex, and optimized for minimum overhead, both in bytes and in latency.

WebSockets is TCP for the web-browser, except with a more robust and much easier

to use API. Suddenly, our client is able to implement any network protocol directly in

the browser, which opens up an entire new world of possibilities. An XMPP chat client?

Easy. Need to connect your client to a custom binary protocol deployed on your existing

network? No problem! Even better, you can script, style, and deploy these clients directly

in the browser with all the web authoring tools you already know, love, and use.

The browser of yesterday talked to an HTTP server. With WebSockets, the browser

can talk to anyone and implement any protocol: complete the HTTP handshake,

upgrade the connection, and you are off to the races. We are no longer talking about

building slightly better or more interactive pages. With WebSockets we can build entirely

new types of apps and experiences that can be delivered to your users today, directly in

their browser.

This book provides a great from-the-ground-up discussion of what WebSockets are,

what problems they are helping us to solve, as well as a number of practical examples

that will get you up and running in no time. You will be pleasantly surprised how easy

it is to work with WebSocket and how much you can accomplish with very little code.

Working with WebSockets is a blast, and this book by Vanessa, Frank, and Peter is a

fitting guide. Enjoy!