Ubuntu

Last reviewed on 2026-05-13 Reference
In short
  • Ubuntu is a Debian-based Linux distribution published by Canonical Ltd.
  • New interim versions are released every six months (April and October); every fourth release is a long-term support (LTS) version, kept supported for five years.
  • There are official editions for desktop, server, cloud, IoT and several alternative desktop environments (Kubuntu, Xubuntu, and so on).
  • For installation, see the step-by-step installation guide; for distribution-level context, see the Ubuntu reference page.

About the project

Ubuntu is one of the most widely used desktop Linux distributions and a common choice for cloud and server deployments. It is developed by Canonical Ltd, a commercial company, in collaboration with a large volunteer community. The first Ubuntu release came out in October 2004; the distribution is built on top of Debian and shares its package format and most of its tooling.

From a user's perspective, Ubuntu is characterised by a predictable release cadence, a focus on out-of-box desktop usability, and good documentation. From a maintainer's perspective, the project follows Debian for the base system, layers Canonical-developed software (Snap, Livepatch, MAAS, LXD/Incus, and so on) on top, and operates a parallel set of repositories and security advisories.

Release model

Ubuntu releases follow a six-month cadence:

  • Interim releases come out in April and October every year. They include the latest software but are supported for nine months only. Version numbers are YY.MM, so an October 2025 release would be 25.10.
  • LTS releases come out every two years, always in April of an even-numbered year. They get five years of standard support from Canonical, plus an additional five years of extended security maintenance through Ubuntu Pro. Their version numbers end in .04 of an even year.

This means that at any given time, there are usually two or three Ubuntu LTS releases under active support, plus the most recent interim release if one exists.

Each release also has a codename: an alliterative pairing of an adjective and an animal, advancing alphabetically (Bionic Beaver, Focal Fossa, Jammy Jellyfish, Noble Numbat, and so on). Codenames are largely cosmetic but appear in repository configuration, so it's worth knowing the one for the version you run.

Official editions

"Ubuntu" usually means Ubuntu Desktop. Canonical also publishes several other editions:

Ubuntu Desktop

The flagship desktop edition with the GNOME desktop environment. Aimed at general-purpose laptop and workstation use.

Ubuntu Server

A minimal install image for servers. No graphical environment by default; intended for headless deployments.

Ubuntu Cloud

Pre-built images for public cloud providers and virtualisation platforms. Available for the major cloud vendors.

Ubuntu Core

A minimal, transactional, all-snap variant aimed at IoT and embedded devices. Updates are atomic and reversible.

In addition, several officially recognised "flavours" of Ubuntu use different default desktop environments while sharing the same package base:

  • Kubuntu — KDE Plasma desktop.
  • Xubuntu — Xfce, light on resources.
  • Lubuntu — LXQt, intended for older hardware.
  • Ubuntu MATE — the MATE desktop, a continuation of the GNOME 2 design.
  • Ubuntu Budgie — the Budgie desktop.
  • Ubuntu Studio — bundled audio, video and graphics production tools.
  • Edubuntu — educational software bundle.

Software model

Ubuntu uses Debian's apt package manager and .deb package format. The bulk of the software in Ubuntu is inherited from Debian and rebuilt with Ubuntu-specific patches where needed.

The distribution organises packages into four repositories:

  • main — supported free software, maintained by Canonical.
  • restricted — proprietary drivers for which Canonical provides support.
  • universe — community-maintained free software (most of what's available).
  • multiverse — software with copyright or legal restrictions.

Canonical also develops Snap, a sandboxed application packaging system that lives alongside apt. Snap packages are distributed through the central Snap Store. Some applications on Ubuntu (notably Firefox on recent releases) are shipped as Snaps by default; this is convenient for distribution but has been the source of some community debate. Flatpak, the alternative cross-distribution sandboxed packaging system, can be installed alongside.

Ubuntu Pro and the commercial offering

Canonical offers a commercial subscription called Ubuntu Pro that extends the support window for LTS releases beyond five years, provides additional security coverage for universe-repository packages, and bundles features such as kernel livepatching and compliance tooling. Ubuntu Pro is free for personal and small-scale use under a limit set by Canonical; commercial use requires a paid subscription.

The terms of Ubuntu Pro change occasionally; the authoritative reference is always ubuntu.com/pro.

Following the project

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