Source
Linux currently 29.1%
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From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
Community icon by Alpár-Etele Méder, licensed under CC BY 3.0
Norwegian government loves windows, so yea, I really doubt it. (by it, I mean the government using Ubuntu thing)
Source: I used to work for the Norwegian government
edit: added explanation to "it", so not to be as confusing to what I refered to.