As one of the earliest operating systems based on the Linux kernel, it was decided that Debian was to be developed openly and freely distributed in the spirit of the GNU Project. This decision drew the attention and support of the Free Software Foundation, which sponsored the project for one year from November 1994 to November 1995.[9] Upon the ending of the sponsorship, the Debian Project formed the non-profit organisation Software in the Public Interest.

Debian is a Unix-like computer operating system that is composed entirely of free software and packaged by a group of individuals participating in the Debian Project.  The Debian Project was first announced in 1993 by Ian Murdock and the first stable release was made in 1996.  The project’s work is carried out over the Internet by a team of volunteers guided by the Debian Project Leader and three foundational documents: the Debian Social Contract, the Debian Constitution, and the Debian Free Software Guidelines. New distributions are updated continually, and the next candidate is released after a time-based freeze.

While all Debian releases are derived from the GNU Operating System and use the GNU userland and the GNU C Library (glibc), other kernels aside from the Linux kernel are also available, such as those based on BSD kernels and the GNU Hurd microkernel.