Microsoft Open XML: Open But NOT So Open?
Looks like Microsoft is trying to put open standards on the background. Well, it's the nature of their business. They are smart, and they make tons of money.
Microsoft is only doing this because they are facing competition from the likes of Adobe and the emerging OpenDocument standard. Microsoft would certainly prefer for the world to use their proprietary file formats, such as .doc (Word for Windows), .xls (Excel) and .ppt (PowerPoint). As long as most people are using these closed formats, it becomes much more difficult for alternatives, such as OpenOffice.org and StarOffice, and in the broader sense, Linux, to gain traction.
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Is Microsoft Open XML Really Open?