How to find out what version of Ubuntu or Debian you are running
On these two distributions of Linux, you can type:
cat /etc/issue
On Ubuntu, but not Debian, you can also type:
cat /etc/lsb-release
...and you will get more verbose version information.
Tested on Ubuntu 10.10 and Debian 4 and 5 (apparently :-)
I have recently installed ubuntu 11.04. My friend just asked me what beta I am using. How can I find out?
How can I know what version of ubuntu I'm running? - Ask Ubuntu - Stack Exchange