Debian
The Debian Project is an association of individuals who have made common cause to create a free operating system. This operating system is called Debian.
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Slackware Linux
The Official Release of Slackware Linux by Patrick Volkerding is an advanced Linux operating system, designed with the twin goals of ease of use and stability as top priorities. Including the latest popular software while retaining a sense of tradition, providing simplicity and ease of use alongside flexibility and power, Slackware brings the best of all worlds to the table.