Release end of life
When an Ubuntu release reaches its “end of life” it receives no further maintenance updates, including critical security upgrades. It is highly recommended that you upgrade to a recent version of Ubuntu at this point.
This command will print the exact status of your system.
For information on previous and upcoming releases and please see the Ubuntu wiki for more details.
Nine years and 18 releases — and all on time
Standard Ubuntu releases are supported for 9 to 18 months. Previous Ubuntu LTS (Long Term Support) releases are now supported for five years on both the desktop and the server. During that time, there will be security fixes and other critical updates.