The primary site for the Linux kernel source, linux information and troubleshooting.
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Super-fast and great-looking, Ubuntu is a secure, intuitive operating system that powers desktops, servers, netbooks and laptops. Ubuntu is, and always will be, absolutely free.
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Comprehensive information and resources about the Linux Operating System.
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Central source for Linux information, software, documentation, how-tos and answers across the server, desktop/netbook, mobile, and embedded areas. San Francisco.
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The GNU Project was launched in 1984 to develop a complete Unix-like operating system which is free software. Boston.