Browser-based apps - HTML5 in Action - page 46

Part 2. Browser-based apps
For a very long time developers were processing everything—form validation, file manage-
ment, storage, messaging, and other vital application functionality—on the server. Server-
side processing was a great idea for security reasons, lack of user processing power, and
many other issues. There were workarounds through technologies such as Flash and Java,
but the mobile market explosion revealed unanticipated limitations that HTML5 is aiming
to fix.
Thanks to major advances in JavaScript processing power and new W3C standards, you can
now perform server-side tasks through a user's browser (aka client-side). Performing com-
plex tasks through browsers saves tons of money on server costs, allows startups to easily
create complex apps, and creates seemingly instant application responses during heavy load
times. It also opens up a completely different thought process on application development
and deployment to mobile and desktop. And they can both be done at the same time if you
play your cards right.
Many popular web applications use HTML5's application features. Google Drive, for ex-
ample, uses a new storage technology known as the Indexed Database API. You've probably
also used HTML5's WebSockets, forms, and many other features that we'll be covering
throughout this section. By the time you've completed part 2 ( chapters 2 - 5 ), you'll know
enough to put together a small application with minimal server usage.