See http://www.debian.org/ for information about Debian GNU/Linux.

This site is a repository for old Debian releases. For new releases
please see http://ftp.debian.org/debian/.

The following releases are archived on this site:

Archive          Releases              Directory
Debian           buzz, rex, bo, hamm,
                 slink, potato, woody,
                 sarge, etch, lenny    debian/
Debian Security  slink, potato, woody,
                 sarge, etch, lenny    debian-security/
Debian Non-US    slink, potato, woody  debian-non-US/
AMD64            sarge                 debian-amd64/
Debian Volatile  sarge, etch, lenny    debian-volatile/
Debian Backports sarge, etch, lenny    backports.org/

Look at the individual directories README file for more information.