For system, network and cloud administrators
I came across a lot of situations where I needed to know the exact version of the OS I was using. Mainly, because of the dependencies involved (Python, PHP, MySQL, etc).
So, open up a terminal and use the following commands in order to view the exact version of your Linux operating system.
lsb_release -d
lsb_release -a
rpm -q centos-release
hostnamectl
rpm -q fedora-release-common
rpm -q fedora-release-workstation
cat /etc/redhat-release
cat /etc/os-release
cat /etc/os-release