Released on April 17th, 2014, the Ubuntu 14.04 (Trusty Tahr) was an LTS (Long Term Support) version supported with security and software updates, as well as regular maintenance releases (the last one being Ubuntu 14.04.6, released on March 5th, 2019) for a total of five years, until April 25th, 2019, when Canonical announced the availability of the extended maintenance support.
Now that Ubuntu 14.04 (Trusty Tahr) will no longer receive security patches, nor software updates, users can choose to either upgrade to a supported release, such as the Ubuntu 16.04 LTS (Xenial Xerus) or Ubuntu 18.04 LTS (Bionic Beaver), or keep their Ubuntu 14.04 installations updated by purchasing the Extended Security Maintenance (ESM) package from Canonical.
We encourage all Ubuntu 14.04 users to upgrade their systems to the Ubuntu 18.04 LTS release, which will be supported until April 2023. However, the upgrade is done in stages via the Ubuntu 16.04 LTS release, which will be supported until April 2021.
Submitted by: Arnfried Walbrecht