2001: After some delays, Linux 2.4 is released. With Linux 2.4's vastly improved support for clustering, multiple processors and large memory space, Linux becomes competitive with Solaris and other high-end server operating systems.
2003: SCO, formed from the old SCO Unix company and the Caldera Linux business, turns its back on its Linux history and sues IBM and other companies and tries to prove that Linux is a copy of Unix. The company fails, but for years its FUD bedevils Linux's commercial acceptance.
2004: Ubuntu is created. Built on top of Debian Linux, Ubuntu is probably used on more Linux desktops than any other desktop distribution.
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