Ubuntu 14.04, named "Trusty Tahr" is a Long Term Support release of Ubuntu Linux (released in April 2014). Note that http://askubuntu.com is specifically dedicated to Ubuntu questions.
Ubuntu 14.04, named "Trusty Tahr" is a Long Term Support (LTS) release of Ubuntu Linux. LTS releases receive updates for 5 years and have available paid support from Canonical. The version number comes from the year and month of release (April of 2014).