Ubuntu Releases
Version Released Name End of Support 4.10 2004-10-20 Warty Warthog 2006-04-30 5.04 2005-04-08 Hoary Hedgehog 2006-10-31 5.10 2005-10-13 Breezy Badger 2007-04-13 6.06 LTS 2006-06-01 Dapper Drake 2009-06 desktops, 2011-06 servers 6.10 2006-10-26 Edgy Eft 2008-04-25 7.04 2007-04-19 Feisty Fawn 2008-10 7.10 2007-10-18 Gutsy Gibbon 2009-04 8.04 LTS 2008-04-24 Hardy Heron 2011-04 desktops, 2013-04 servers 8.10 2008-10-30 Intrepid Ibex 2010-04 9.04 2009-04-23 Jaunty Jackalope 2011-10 9.10 2009-10-29 Karmic Koala 2011-04 10.04 LTS 2010-04-29 Lucid Lynx 2013-04 desktops, 2015-04 servers 10.10 2010-10-10 Maverick Meerkat 2012-04 11.04 2011-04-28 Natty Narwhal 2012-10 11.10 2011-10-13 Oneiric Ocelot 2013-04 12.04 LTS 2012-04-26 Precise Pangolin 2017-04 both desktops and servers 12.10 2012-10-18 Quantal Quetzal 2014-04 both desktops and servers 13.04 2013-04-18 Raring Ringtail 2014-01 both desktops and servers 13.10 2013-10-17 Saucy Salamander 2014-07 both desktops and servers 14.04 LTS 2014-04-17 Trusty Tahr 2019-04 14.10 2014-10-23 Utopic Unicorn 2015-07 15.04 2015-04-23 Vivid Vervet 2016-01 15.10 2015-10-22 Wily Werewolf 2016-07 16.04 LTS 2016-04-21 Xenial Xerus 2021-04 16.10 2016-10-13 Yakkety Yak 2017-07-20 17.04 2017-04-13 Zesty Zapus 2018-01 17.10 2017-10-19 Artful Aardvark 2018-07 18.04 LTS 2018-04-26 Bionic Beaver 2023-04 18.10 2018-10-18 Cosmic Cuttlefish2019-07 19.04 2019-04-18 Disco Dingo 2020-01 19.10 2019-10-17 Eoan Ermine TBA
The above table applies equally to Ubuntu Desktop, Ubuntu Business Desktop Remix, Ubuntu Cloud, Ubuntu GNOME, Ubuntu for Android, Ubuntu Server, Ubuntu Studio, Ubuntu Touch, Ubuntu TV, Edubuntu, Fluxbuntu, Kubuntu, Lubuntu, Medibuntu, Mythbuntu, UbuntuKylin, Xubuntu, Aurora, Baltix, BackBox, BackTrack, BlankOn, BuildX, Bodhi Linux Cubuntu, dyne:bolic, EasyPeasy, ElementOS, elementary OS, Emmabuntus, Galsoft Linux, GendBuntu, Goobuntu, gOS, Guadalinex, Iskolinux, Joli OS, HP Mi, Impi Linux, Karoshii, Kuki Linux, LiMux, Linux Mint, LinuxMCE, LinuxLTE, LliureX, MAX, Molinux, Moon OS, Nova, Netrunner, OpenGEU, Peppermint OS, Pinguy OS, Poseidon Linux, PUD, Qimo 4 Kids, Sabily, Super OS, Trisquel GNU/Linux, TurnKey Linux Virtual Appliance Library, UberStudent, Ubuntu MATE, Vinux, ZevenOS, and no doubt various other variants, some officially sponsored by Canonical, Ltd. and others not. All of those branded variants share a common OS core package set, which in effect is what gets the *buntu version number and branch name.
Early on, Canonical established the convention that each version number would comprise the one-or-two-digit year, a decimal point, then the two-digit month in which release occurred. Thus, because initial release "Warty Warthog" ended up being released in October 2004, it became version 4.10. Because release schedules can slip, a release that's predicted to emerge as "10.02" (on account of an expected February 2010 release window) and referred to by that number in advance of release can end up bearing a "higher" (later-date) number reflecting scheduling slippage.
Baseline paid-support duration is 18 months from release, except for releases designated "LTS" (Long Term Support), often appended as a suffix to qualifying release versions, e.g., "6.06 LTS".
The whimsical names were at first, if memory serves, intended as beta tags, but have become traditional: The form is "adjective animalname", with the short form being just the adjective.