http://googleblog.blogspot.com/2008/07/protocol-buffers-our-open-source-data.html
and
Google Open Source Blog: Protocol Buffers: Google’s Data Interchange Format
XML? No, that wouldn’t work. As nice as XML is, it isn’t going to be efficient enough for this scale. When all of your machines and network links are running at capacity, XML is an extremely expensive proposition. Not to mention, writing code to work with the DOM tree can sometimes become unwieldy.
By sticking to a simple lists-and-records model that solves the majority of problems and resisting the desire to chase diminishing returns, we believe we have created something that is powerful without being bloated. And, yes, it is very fast – at least an order of magnitude faster than XML.
Technology going in a big circle? I remember when everything was going to XML forever — Office 2003, for example. Now it’s back to the future with a simpler, more stripped down technology …
