It has 95% market share in the productivity software market, 75% share in the operating system market and approximately 75% share in the server software market.

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Open source software such as Apache Web server and the Linux server operating system have become popular systems to run not only on network servers, but also on server appliances (servers dedicated to single tasks such as e-mail and Web site hosting).

CNN: Red Hat to support "all things open source"

Lesswatts.org will host a group of software developers working to build Linux operating system upgrades that use server hardware more efficiently and save energy.

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