Although Ubuntu is relatively new, it builds on the rich history and deep roots of the venerable Debian project, one of the oldest and most influential Linux distributions. The fate of the two popular flavors of Linux is as inextricably bound as their respective histories.
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Ubuntu still depends heavily on upstream Debian in many ways, but the relationship between the two distributions hasn't always been positive. Ubuntu's early successes put some strain on its ties with Debian and led to accusations of parasitism and inadequate reciprocation. The Ubuntu community has taken important steps over the years to ease tensions and address the conflict.
When the controversy first began to emerge in 2005, Debian founder Ian Murdock commented that the mutual success of Debian and Ubuntu would depend on the ability to ensure ongoing compatibility and collaboration between the distributions.