Ubuntu 15.04, named "Vivid Vervet" is a non-LTS (Long Term Support) release of Ubuntu Linux. Released in April 2015, its official support ended on February 4, 2016. Note that http://askubuntu.com is specifically dedicated to Ubuntu questions.
Ubuntu 15.04, named "Vivid Vervet" is a non-LTS (Long Term Support) release of Ubuntu Linux (released in April 2015). Only use this tag if your question is version-specific. Note that http://askubuntu.com is specifically dedicated to Ubuntu questions.