Linux lacks any clear-cut system for determining which is the most popular or the best distribution, or which desktop environment is used more than others. That may be one of the major frustrations among Linux developers trying to spread the word about adopting the Linux desktop instead of Microsoft Windows or Apple's OS X.

Linux, like the countless denominations of religions, is a product of technology, ideology and endless options. Unlike its competitors, the Linux OS is not sold. It just is available to those who know about it.

One reason for the apparent uncertainty surrounding Linux is that no single company markets Linux as a product.

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