Debian in the context of Linux distribution

Mozilla Firefox, or simply Firefox, is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary, the Mozilla Corporation. It uses the Gecko rendering engine to display web pages, which implements current and anticipated web standards. Firefox is available for Windows 10 or later versions of Windows, macOS, and Linux. Its unofficial ports are available for various Unix and Unix-like operating systems, including FreeBSD, OpenBSD, NetBSD, and other operating systems, such as ReactOS. It is the default, pre-installed browser on Debian, Ubuntu, and other Linux distros. Firefox is also available for Android and iOS. However, as with all other iOS web browsers, the iOS version uses the WebKit layout engine instead of Gecko due to platform requirements. An optimized version was also available on the Amazon Fire TV as one of the two main browsers available with Amazon's Silk Browser, until April 30, 2021, when Firefox would be discontinued on that platform. Firefox is the spiritual successor of Netscape Navigator, as the Mozilla community was created by Netscape in 1998, before its acquisition by AOL. Firefox was created in 2002 under the codename "Phoenix" by members of the Mozilla community who desired a standalone browser rather than the Mozilla Application Suite bundle. During its beta phase, it proved to be popular with its testers and was praised for its speed, security, and add-ons compared to Microsoft's then-dominant Internet Explorer 6. It was released on November 9, 2004, and challenged Internet Explorer's dominance with 60 million downloads within nine months. In November 2017, Firefox began incorporating new technology under the code name "Quantum" to promote parallelism and a more intuitive user interface.

Firefox usage share grew to a peak of 32.21% in November 2009, with Firefox 3.5 overtaking Internet Explorer 7, although not all versions of Internet Explorer as a whole; its usage then declined in competition with Google Chrome. As of February 2025, according to StatCounter, it had a 6.36% usage share on traditional PCs (i.e. as a desktop browser), making it the fourth-most popular PC web browser after Google Chrome (65%), Microsoft Edge (14%), and Safari (8.65%).

Linux (/ˈlɪnʊks/ LIN-uuks) is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution (distro), which includes the kernel and supporting system software and libraries—most of which are provided by third parties—to create a complete operating system, designed as a clone of Unix and released under the copyleft GPL license.

Thousands of Linux distributions exist, many based directly or indirectly on other distributions; popular Linux distributions include Debian, Fedora Linux, Linux Mint, Arch Linux, and Ubuntu, while commercial distributions include Red Hat Enterprise Linux, SUSE Linux Enterprise, and ChromeOS. Linux distributions are frequently used in server platforms. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses and recommends the name "GNU/Linux" to emphasize the use and importance of GNU software in many distributions, causing some controversy. Other than the Linux kernel, key components that make up a distribution may include a display server (windowing system), a package manager, a bootloader and a Unix shell.

Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Open-source software may be developed in a collaborative, public manner. Open-source software is a prominent example of open collaboration, meaning any capable user is able to participate online in development, making the number of possible contributors indefinite. The ability to examine the code facilitates public trust in the software.

Open-source software development can bring in diverse perspectives beyond those of a single company. A 2024 estimate of the value of open-source software to firms is $8.8 trillion, as firms would need to spend 3.5 times the amount they currently do without the use of open source software.

Ubuntu (/ʊˈbʊntuː/ uu-BUUN-too) is a Linux distribution based on Debian and composed primarily of free and open-source software. Developed by the British company Canonical and a community of contributors under a meritocratic governance model, Ubuntu is released in multiple official editions: Desktop, Server, and Core for IoT and robotic devices.

Ubuntu is published on a six-month release cycle, with long-term support (LTS) versions issued every two years. Canonical provides security updates and support until each release reaches its designated end-of-life (EOL), with optional extended support available through the Ubuntu Pro and Expanded Security Maintenance (ESM) services.

SteamOS is a gaming-focused operating system released by Valve that incorporates the company's video game storefront, Steam. Based on Arch Linux and built specifically to support Steam, it is the default Linux distribution for Valve's line of gaming hardware, including the Steam Deck, Steam Machine, and Steam Frame. Beginning in 2025, Valve expanded official support to include third-party devices designated as "SteamOS Compatible", such as handhelds like the Lenovo Legion Go and Asus ROG Ally. It can also be installed on personal computers without official support from Valve. The core operating system is free and open-source software, while the Steam client remains proprietary.

SteamOS was first released in 2013, with versions 1.0 and 2.0 based on Debian and designed primarily as a client for streaming games over a local network from a gaming PC, with limited support for native gameplay. Valve promoted the platform as part of a broader effort to expand Linux gaming. In 2022, Valve introduced SteamOS 3.0 alongside the launch of the Steam Deck. This version transitioned to an Arch Linux base which used a rolling release model that Valve felt was better suited for hardware support. It has a dual‑mode interface: a console‑style mode powered by Steam's Big Picture UI, and a KDE Plasma desktop environment for traditional computing use. SteamOS 3.0 also incorporates Valve’s Proton compatibility layer, enabling many Windows games to run on Linux.

Linux Mint is a community-developed Linux distribution based primarily on Ubuntu, with an alternative version based on Debian known as Linux Mint Debian Edition (LMDE). It is available for x86-64 systems, while LMDE supported the IA-32 architecture until 2025. First released in 2006, Linux Mint is often noted for its ease of use, out-of-the-box functionality, and appeal to desktop users. It comes bundled with a selection of free and open-source software. The default desktop environment is Cinnamon, developed by the Linux Mint team, with MATE and Xfce available as alternatives.

Debian releases do not follow a fixed schedule. Recent releases have been made around every two years by the Debian Project. The most recent version of Debian is Debian version 13, codename "Trixie". The next up and coming release of Debian is Debian 14, codename "Forky".

Debian always has at least three active branches at any time: "stable", "testing" and "unstable". The stable branch is considered the primary release and what most people refer to when talking about Debian. The testing branch contains packages that have been imported from unstable. Testing has significantly more up-to-date packages than stable and is frozen some time before a release to become the next version of Debian. The unstable release (also known as Sid) is the branch where active development takes place. It is the most volatile version of Debian.