uname linux

 uname

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uname (short for unix name) is a computer program in Unix and Unix-like computer operating systems that prints the name, version and other details about the current machine and the operating system running on it.

comment 1 :
uname -a

Darwin Roadrunner.local 10.3.0 Darwin Kernel Version 10.3.0: Fri Feb 26 11:58:09 PST 2010; root:xnu-1504.3.12~1/RELEASE_I386 i386

comment 2 :
uname -s

Linux

comment 3 :
uname -r

x.xx.x-xx-generic

comment 4 :
uname -v

xx-xx.xx-ubuntu smp Fri Mar 15 10:10:10 UTC 2011