cat /etc/issue
Novell SuSE
cat/etc/SuSE-release
Red Hat
cat /etc/redhat-release, /etc/redhat_version
Fedora
cat /etc/fedora-release
Slackware
cat /etc/slackware-release, /etc/slackware-version
Debian
cat /etc/debian_release, /etc/debian_version,
Mandrake
cat /etc/mandrake-release
Yellow dog
cat /etc/yellowdog-release
Sun JDS
cat /etc/sun-release
Solaris/Sparc
cat /etc/release
Gentoo
cat /etc/gentoo-release