It marks the fourth long-term support (LTS) release of the world's favourite free operating system, with maintenance updates guaranteed for five years.

ENGADGET: Ubuntu 12.04 LTS Precise Pangolin hits the web, with HUD in tow

Until now, people who downloaded non-LTS (long-term support) versions of Ubuntu were treated to a lengthy support period -- a full 18 months.

ENGADGET: Canonical cuts support for non-LTS versions of Ubuntu, users now get nine months of bug fixes