osrelease, ostype & version

file: /proc/sys/kernel/osrelease, ostype & version
variable: kernel.osrelease, ostype & version
Official reference
# cat osrelease
# cat ostype
# cat version
#5 Wed Feb 25 21:49:24 MET 1998

The files osrelease and ostype should be clear enough. Version needs a little more clarification however. The ‘#5’ means that this is the fifth kernel built from this source base and the date behind it indicates the time the kernel was built. The only way to tune these values is to rebuild the kernel :-)