Free and open-source software in the context of Media Player Classic

Krita (/ˈkriːtə/ KREE-tə) is a free and open-source raster graphics editor designed primarily for digital art and 2D animation. Originally created for Linux, the software also runs on Windows, macOS, Haiku, Android, and ChromeOS, and features an OpenGL-accelerated canvas, colour management support, an advanced brush engine, non-destructive layers and masks, group-based layer management, vector artwork support, and switchable customisation profiles.

The software is also available as paid software, distributed on Microsoft Store, Steam, Epic Games Store, and Mac App Store. Payments support the development of the software. The paid version has automatic updates.

A personal computer (PC), or simply computer, is a computer designed for personal use. It is typically used for tasks such as word processing, internet browsing, email, multimedia playback, and gaming. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or technician. Unlike large, costly minicomputers and mainframes, time-sharing by many people at the same time is not used with personal computers. The term "home computer" has also been used, primarily in the late 1970s and 1980s. The advent of personal computers and the concurrent Digital Revolution have significantly affected the lives of people.

Institutional or corporate computer owners in the 1960s had to write their own programs to do any useful work with computers. While personal computer users may develop their applications, usually these systems run commercial software, free-of-charge software ("freeware"), which is most often proprietary, or free and open-source software, which is provided in ready-to-run, or binary form. Software for personal computers is typically developed and distributed independently from the hardware or operating system manufacturers. Many personal computer users no longer need to write their programs to make any use of a personal computer, although end-user programming is still feasible. This contrasts with mobile systems, where software is often available only through a manufacturer-supported channel and end-user program development may be discouraged by lack of support by the manufacturer.

Blender is a free and open-source 3D computer graphics software tool set that runs on Windows, macOS, Linux, BSD, Haiku, and IRIX. It is used for creating animated films, visual effects, art, 3D-printed models, motion graphics, interactive 3D applications, and virtual reality. It is also used in creating models for video games.

Blender was used to produce the Academy Award-winning film Flow (2024).

Proprietary software is software that grants its creator, publisher, or other rightsholder or rightsholder partner a legal monopoly by modern copyright and intellectual property law to exclude the recipient from freely sharing the software or modifying it, and—in some cases, as is the case with some patent-encumbered and EULA-bound software—from making use of the software on their own, thereby restricting their freedoms.

Proprietary software is a subset of non-free software, a term defined in contrast to free and open-source software; non-commercial licenses such as CC BY-NC are not deemed proprietary, but are non-free. Proprietary software may either be closed-source software or source-available software.

Google Chrome is a cross-platform web browser developed by Google. It was first released in 2008 for Microsoft Windows, built with free software components from Apple WebKit and Mozilla Firefox. Versions were later released for Linux, macOS, iOS, iPadOS, and also for Android, where it is the default browser. The browser is also the main component of ChromeOS, on which it serves as the platform for web applications.

Most of Chrome's source code comes from Google's free and open-source software project known as Chromium, but Chrome is licensed as proprietary freeware. WebKit was the original rendering engine, but Google eventually forked it to create the Blink engine; all Chrome variants except iOS used Blink as of 2017.

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%).

Android is an operating system based on a modified version of the Linux kernel and other open-source software, designed primarily for touchscreen-based mobile devices such as smartphones and tablet computers. Android has historically been developed by a consortium of developers known as the Open Handset Alliance, but its most widely used version is primarily developed by Google. First released in 2008, Android is the world's most widely used operating system; it is the most used operating system for smartphones, and also most used for tablets; the latest version, released on June 10, 2025, is Android 16.

At its core, the operating system is known as the Android Open Source Project (AOSP) and is free and open-source software (FOSS) primarily licensed under the Apache License. However, most devices run the proprietary Android version developed by Google, which ships with additional proprietary closed-source software pre-installed, most notably Google Mobile Services (GMS), which includes core apps such as Google Chrome, the digital distribution platform Google Play, and the associated Google Play Services development platform. Firebase Cloud Messaging is used for push notifications. While AOSP is free, the "Android" name and logo are trademarks of Google, who restrict the use of Android branding on "uncertified" products. The majority of smartphones based on AOSP run Google's ecosystem—which is known simply as Android—some with vendor-customized user interfaces and software suites, for example One UI. Numerous modified distributions exist, which include competing Amazon Fire OS, community-developed LineageOS; the source code has also been used to develop a variety of Android distributions on a range of other devices, such as Android TV for televisions, Wear OS for wearables, and Meta Horizon OS for VR headsets.

Open-source licenses are software licenses that allow content to be used, modified, and shared. They facilitate free and open-source software (FOSS) development. Intellectual property (IP) laws restrict the modification and sharing of creative works. Free and open-source licenses use these existing legal structures for an inverse purpose. They grant the recipient the rights to use the software, examine the source code, modify it, and distribute the modifications. These criteria are outlined in the Open Source Definition.

After 1980, the United States began to treat software as a literary work covered by copyright law. Richard Stallman founded the free software movement in response to the rise of proprietary software. The term "open source" was used by the Open Source Initiative (OSI), founded by free-software developers Bruce Perens and Eric S. Raymond. "Open source" emphasizes the strengths of the open development model rather than software freedoms. While the goals behind the terms are different, open-source licenses and free-software licenses describe the same type of licenses.

A free-software license is a notice that grants the recipient of a piece of software extensive rights to modify and redistribute that software. These actions are usually prohibited by copyright law, but the rights-holder (usually the author) of a piece of software can remove these restrictions by accompanying the software with a software license which grants the recipient these rights. Software using such a license is free software (or free and open-source software) as conferred by the copyright holder. Free-software licenses are applied to software in source code and also binary object-code form, as the copyright law recognizes both forms.

Opus is a free and open source lossy audio coding format developed by the Xiph.Org Foundation and standardized by the Internet Engineering Task Force, designed for efficient low-latency encoding of both speech and general audio. Due to its lower latency relative to other standard codecs, Opus finds specific use cases in real-time interactive communication for low-end embedded processors. Opus replaces both Vorbis and Speex for new applications.

Opus combines the speech-oriented LPC-based SILK algorithm and the lower-latency MDCT-based CELT algorithm, switching between or combining them as needed. Bitrate, audio bandwidth, complexity, and algorithm choice can be adjusted for each individual frame. Opus has low algorithmic delay (26.5 ms by default) ideal for use as part of a real-time communication link, networked music performances, and live lip sync; by trading off quality or bitrate, the delay can be further reduced down to 5 ms. Its delay thus is significantly lower compared to competing codecs, which require well over 100 ms. Opus remains competitive with these formats in terms of quality per bitrate.

KDE is an international free software community that develops free and open-source software. As a central development hub, it provides tools and resources that enable collaborative work on its projects. Its products include the KDE Plasma graphical shell, KDE Frameworks, and the KDE Gear range of applications including Kate, digiKam, and Krita. Many KDE applications are cross-platform and can run on Unix and Unix-like operating systems as well as Microsoft Windows. KDE is legally represented by KDE e.V. based in Germany, which also owns the KDE trademarks and funds the project.

Haiku, originally OpenBeOS, is a free and open-source operating system for personal computers. It is a community-driven continuation of BeOS and aims to be binary-compatible with it, but is largely a reimplementation with the exception of certain components like the Deskbar. The Haiku project began in 2001, supported by the nonprofit Haiku Inc., and the operating system remains in beta.

MythTV is a free and open-source digital video recorder and media center application with a simplified "10-foot user interface" design for the living room TV. It turns a computer with the necessary hardware into a network streaming digital video recorder, a digital multimedia home entertainment system, or home theater personal computer. It can be considered a free and open-source alternative to TiVo or Windows Media Center. It runs on various operating systems, primarily Linux, macOS, and FreeBSD.

Xfce (pronounced as four individual letters, /ɛks ɛf siː iː/) is a free and open-source desktop environment for Linux and other Unix-like operating systems.

Xfce aims to be fast and lightweight while still visually appealing and easy to use. The desktop environment is designed to embody the traditional Unix philosophy of modularity and re-usability, as well as adherence to standards; specifically, those defined at freedesktop.org.

Freeciv is a single- and multiplayer turn-based strategy game for workstations and personal computers inspired by the proprietary Sid Meier's Civilization series. It is available for most desktop computer operating systems and available in an online browser version. Released under the GNU GPL-2.0-or-later, Freeciv is free and open-source software. The game's default settings are closest to Civilization II, in both gameplay and graphics, including the units and the isometric grid. However, with a lot of multiplayer games being played in longturn communities, rulesets and additional variants have evolved away from the original ruleset. Freeciv is playable online on various public and private servers.

Players take the role of tribal leaders in 4000 B.C. who must guide their peoples through the centuries. Over time, new technologies are discovered, which allow the construction of new city buildings and the deployment of new units. Players can wage war on one another or form diplomatic relationships.

Vorbis is a free and open-source software project headed by the Xiph.Org Foundation. The project produces an audio coding format and software reference encoder/decoder (codec) for lossy audio compression, libvorbis. Vorbis is most commonly used in conjunction with the Ogg container format and it is therefore often referred to as Ogg Vorbis.

Version 1.0 of Vorbis was released in May 2000. Since 2013, the Xiph.Org Foundation has stated that the use of Vorbis should be deprecated in favor of the Opus codec, an improved and more efficient format that has also been developed by Xiph.Org.

Commercial software, or, seldom, payware, is a computer software that is produced for sale or that serves commercial purposes. Commercial software can be proprietary software or free and open-source software.