HowTo: Find Linux distribution name and version

#How to check release on Linux / Debian / Ubuntu??

You can use any one of the following method to find out your Linux distribution and name:

#1.] /etc/*-release file.

#2.] lsb_release command.

#3.] /proc/version file.

Method #1: /etc/*-release file

To find out what version of Linux (distro) you are running, enter the following command at the shell prompt:
$ cat /etc/*-release
Sample output from my RHEL v5.x server:

Red Hat Enterprise Linux Server release 5 (Tikanga)

Sample outputs from my Ubuntu Linux v7.10 server:

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=7.10
DISTRIB_CODENAME=gutsy
DISTRIB_DESCRIPTION="Ubuntu 7.10"

Method #2: lsb_release Command To Find Out Linux Distribution Name/Version

The lsb_release command displays certain LSB (Linux Standard Base) and distribution-specific information. Type the following command:

$ lsb_release -a

Sample outputs:

No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 6.0.1 (squeeze)
Release: 6.0.1
Codename: squeeze

How Do I Find Out My Kernel Version?

Type the following command:
$ uname -a
OR
$ uname -mrs
Sample outputs:

Linux 2.6.32-5-amd64 x86_64

Where,

1. Linux - Kernel name
   
2. 2.6.32-5-amd64 - Kernel version number
   
3. x86_64 - Machine hardware name (64 bit)
   

Method #3: /proc/version

Type the following command to see kernel version and gcc version used to build the same:

$ cat /proc/version

Sample outputs:
Linux version 3.2.0-0.bpo.1-amd64 (Debian 3.2.4-1~bpo60+1) (ben@decadent.org.uk) (gcc version 4.4.5 (Debian 4.4.5-8) ) #1 SMP Sat Feb 11 08:41:32 UTC 2012