Ubuntu release cycle is once in 6 months and Long Term Support (LTS) release is once in 2 years. Ubuntu follows version number in the format of YY.MM (i.e.: Year.Month). Here are two ways to find the your Ubuntu installation’s version number.
The Ubuntu version number is stored in two files in /etc path. Once is /etc/issue and another one is /etc/lsb-release. You can just print these files to get the version number. I have shown here my Ubuntu 10.04 version.
$ cat /etc/issueUbuntu 10.04 LTS \n \l
$ cat /etc/lsb-release
DISTRIB_DESCRIPTION=”Ubuntu 10.04 LTS”
Update: Many readers have pointed out other alternative ways to get the version number. I have added these for completeness.
$ lsb_release -dDescription: Ubuntu 10.04 LTS
GUI way of doing it
Method 4: (it loads very slow)
$ uname -aLinux blackgod-laptop 2.6.32-22-generic #36-Ubuntu SMP Thu Jun 3 19:31:57 UTC 2010 x86_64 GNU/Linux
The above output shows,
Host name: blackgod-laptop
Kernel version: 2.6.32-22-generic
Multiprocessor enabled (SMP)
It is 64 bit installation (x86_64).
Hope these tips may be useful for you.