How do I find out what ver­sion of Linux dis­tri­b­u­tion I’m using from the shell prompt?

aptitude install lsb-release

 

lsb_release -a

 

Distributor ID: Debian
Description:    Debian GNU/Linux 6.0.2 (squeeze)
Release:    6.0.2
Codename:   squeeze

Find Out My Linux Dis­tri­b­u­tion Name and Version