How To Find Ubuntu Version

1)
Find ubuntu version using "lsb_release" command

      anusree@anusree-VirtualBox:~$ lsb_release -a
      No LSB modules are available.
      Distributor ID:    Ubuntu
      Description:    Ubuntu 14.04.1 LTS
      Release:    14.04
      Codename:    trusty
      anusree@anusree-VirtualBox:~$