Ubuntu 15.04, the new release, which will be supported for nine months, features LibreOffice 4.4, version 3.19 of the Linux kernel and a switch from Canonical's Upstart init to systemd. "systemd has replaced Upstart as the standard boot and service manager on all Ubuntu flavors except Touch. At the time of the 15.04 release there are no known major problems which prevent booting. The only service which does not currently start is Juju, which will be fixed in a post-release update soon; all other packaged Ubuntu services are expected to work. Upstart continues to control user sessions... You can boot with Upstart once by selecting `Advanced options for Ubuntu' in the GRUB boot menu and starting the `Ubuntu, with Linux ... (upstart)' entry. To switch back permanently, install the upstart-sysv package (this will remove systemd-sysv and ubuntu-standard).

About Ubuntu

Ubuntu is a complete desktop Linux operating system, freely available with both community and professional support. The Ubuntu community is built on the ideas enshrined in the Ubuntu Manifesto: that software should be available free of charge, that software tools should be usable by people in their local language and despite any disabilities, and that people should have the freedom to customise and alter their software in whatever way they see fit. "Ubuntu" is an ancient African word, meaning "humanity to others". The Ubuntu distribution brings the spirit of Ubuntu to the software world.