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The layers of web platforms

It seems that the operating systems are the first layer of flatforms for building multiple applications. But operating systems are not enough for various requirements, and building applications directly upon operating systems layer is just very difficult and hard to transplant.

So, we build applications inside our internet navigators. It is the first layer of web platforms, solve a lot of cross-OS problems. Now, multiple APIs arise and become very popular, such as javascript based libraries, AJAX, Flash, Silverlight etc... Maybe we could play game like Quake 4 inside the Firefox with a 3D engine built by javascript.

There comes the next layer, which is the gadget layer. The web 2.0 websites open their API for third party developers, the typical is Facebook. Applications built on this layer could easily make use of the social networks resources of the platform itself.

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