Raymond Camden - Client-Side Data Storage: Keeping It Local

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Browsers haveslowly and with a lot of growing painsevolved over the past decade to become powerful workhorses. Enhanced layout controls, 3D graphics and gaming, and even music are now within the realm of possibility of the little old browser. One more exciting, although relatively less flashy (no pun intended), feature is client-side data storage. But what do we mean by this?

The typical process by which you navigate the Web hasnt changed since time began: your browser asks for a URL, a web server sends stuff back, you then ask for more stuff, and the web server sends more stuff to you.

You can certainly get more complex and add JavaScript and AJAX to the mix. But even in a fancy web 2.0 application, your browser may be requesting information from the server again and again and again. The reason for this is thatfor all intents and purposesthe browser is an amnesiac. Everything it knows it has to learn from the server.

While this is true in general, it overlooks a powerful alternativestoring data on the browser itself. This enables the browser to skip asking the server for information and to simply retrieve it locally from the users machine. It even affords the chance to manipulate that data for whatever purposes may make sense. That data could then be sent back to the server for updating later.

In summary, this gives the browser:

• Immediate access to data. Even with AJAX being typically much quicker for fetching data, by having the data local to the machine itself access will be even quicker.

• Less network traffic. Instead of constantly fetching data from the server, data can be fetched once and stored for as long as it makes sense. This leads to...

• Less strain on your server. If your server is constantly responding to requests and fetching stuff from a database server, you could overtax your server. By reducing the amount of calls you make, your server does less work.