Ubuntu 16.10 Yakkety Yak

Ubuntu releases are made semiannually by Canonical Ltd, the developers of the Ubuntu operating system, using the year and month of the release as a version number. The first Ubuntu release, for example, was Ubuntu 4.10 and was released on 20 October 2004. Consequently, version numbers for future versions are provisional; if the release is delayed until a different month (or even year) to that planned, the version number will change accordingly.

Ubuntu releases are timed to be approximately one month after GNOME releases, which are in turn about one month after releases of X.Org, resulting in each Ubuntu release including a newer version of GNOME and X.

Every fourth release, in the second quarter of even-numbered years, has been designated as a Long Term Support (LTS) release, indicating that they are supported and receive updates for five years, with paid technical support also available from Canonical Ltd. However the desktop version of LTS releases before 12.04 were supported for only three years. Releases 14.04, and 16.04 are the current LTS releases. Non-LTS releases prior to 13.04 have typically been supported for 18 months, and have always been supported until at least the date of the next LTS release. This has changed, however, for 13.04 and subsequent non-LTS releases, with the support period being halved to 9 months.

Ubuntu releases are also given code names, using an adjective and an animal with the same first letter (e.g. Dapper Drake). With the exception of the first two releases, code names are in alphabetical order, allowing a quick determination of which release is newer. Names are occasionally chosen so that animal appearance or habits reflects some new feature (e.g., "Koala's favourite leaf is Eucalyptus"; see below). Ubuntu releases are often referred to using only the adjective portion of the code name (e.g. Feisty).

Ubuntu 4.10 (Warty Warthog), released on 20 October 2004, was Canonical's first release of Ubuntu, building upon Debian, with plans for a new release every six months and eighteen months of support thereafter. Ubuntu 4.10's support ended on 30 April 2006. Ubuntu 4.10 was offered as a free download and, through Canonical's ShipIt service, was also mailed to users free of charge in CD format.

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