Free and open-source in the context of BSD

A wiki (/ˈwɪki/ WICK-ee) is a form of hypertext publication on the internet which is collaboratively edited and managed by its audience directly through a web browser. A typical wiki contains multiple pages that can either be edited by the public or limited to use within an organization for maintaining its internal knowledge base. Its name derives from the first user-editable website called WikiWikiWeb – wiki (pronounced [wiki]) is a Hawaiian word meaning 'quick'.

Wikis are powered by wiki software, also known as wiki engines. Being a form of content management system, these differ from other web-based systems such as blog software or static site generators in that the content is created without any defined owner or leader. Wikis have little inherent structure, allowing one to emerge according to the needs of the users. Wiki engines usually allow content to be written using a lightweight markup language and sometimes edited with the help of a rich-text editor. There are dozens of different wiki engines in use, both standalone and part of other software, such as bug tracking systems. Some wiki engines are free and open-source, whereas others are proprietary. Some permit control over different functions (levels of access); for example, editing rights may permit changing, adding, or removing material. Others may permit access without enforcing access control. Further rules may be imposed to organize content. In addition to hosting user-authored content, wikis allow those users to interact, hold discussions, and collaborate.

MediaWiki is a free and open-source wiki software originally developed by Magnus Manske and released for use on Wikipedia on January 25, 2002, and further enhanced by Lee Daniel Crocker, after which development has been coordinated by the Wikimedia Foundation. It powers several wiki hosting websites across the Internet, as well as most websites hosted by the Wikimedia Foundation including Wikipedia, Wiktionary, Wikimedia Commons, Wikiquote, Meta-Wiki and Wikidata, which define a large part of the set requirements for the software. Besides its usage on Wikimedia sites, MediaWiki has been used as a knowledge management and content management system on websites such as Fandom, wikiHow and major internal installations like Intellipedia and Diplopedia.

MediaWiki is written in the PHP programming language and stores all text content into a database. The software is optimized to efficiently handle large projects, which can have terabytes of content and hundreds of thousands of views per second. Because Wikipedia is one of the world's largest and most visited websites, achieving scalability through multiple layers of caching and database replication has been a major concern for developers. Another major aspect of MediaWiki is its internationalization; its interface is available in more than 400 languages. The software has hundreds of configuration settings and more than 1,000 extensions available for enabling various features to be added or changed.

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.

The .NET platform (pronounced as "dot net"; formerly named .NET Core) is a free and open-source, managed computer software framework for Windows, Linux, and macOS operating systems. It is a cross-platform successor to the .NET Framework. The project is mainly developed by Microsoft employees by way of the .NET Foundation and is today released under an MIT License.

New versions of the .NET platform are released annually, typically in November. The most recent version of .NET is .NET 10, released in November 2025, which is a long-term support (LTS) version, and is scheduled to receive updates until November 2028.

Mozilla Thunderbird is a free and open-source personal information manager primarily used as an e-mail client with a calendar and contactbook, as well as an RSS feed reader, chat client (IRC/XMPP/Matrix), and news client. Operated by MZLA Technologies Corporation, a subsidiary of the Mozilla Foundation, Thunderbird is an independent, community-driven project that is managed and overseen by the Thunderbird Council, which is elected by the Thunderbird community. As a cross-platform application, Thunderbird is available for Windows, macOS, FreeBSD, Android, and Linux. The project strategy was originally modeled after that of Mozilla's Firefox, and Thunderbird is an interface built on top of that Web browser.

Chromium is a free and open-source web browser project, primarily developed and maintained by Google. It is a widely used codebase, providing the vast majority of code for Google Chrome and many other browsers, including Microsoft Edge, Samsung Internet, and Opera. The code is also used by several app frameworks.

NetBSD is a free and open-source Unix-like operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is available for many platforms, including servers, desktops, handheld devices, and embedded systems.

The NetBSD project focuses on code clarity, careful design, and portability across many computer architectures. Its source code is publicly available and permissively licensed.

In computing, a presentation program (also called presentation software) is a software package used to display information in the form of a slide show. It has three major functions:

• an editor that allows text to be inserted and formatted
• a method for inserting and manipulating graphic images and media clips
• a slide-show system to display the content

Presentation software can be viewed as enabling a functionally-specific category of electronic media, with its own distinct culture and practices as compared to traditional presentation media (such as blackboards, whiteboards and flip charts).

digiKam is a free and open-source image organizer and tag editor written in C++ using the KDE Frameworks.

Vim (/vɪm/ ; short for vi improved) is a free and open-source text editor. Vim provides both a terminal screen user interface as well as a graphical user interface (called gvim).

Vim's documentation describes it as an improved form of the older vi text editor (though it is built from a distinct codebase). In release information, the author originally implied that Vim was an abbreviation for "Vi IMitation", but later, the expansion was changed to "Vi IMproved" because, as described by the author, the functionality had increased beyond that of a clone of vi. Some sources indicate the change happened with v2.0, but conflicting information (including from author) suggests the change happened as early as v2.0 and as late as v3.0.

The GNU Image Manipulation Program, commonly known by its acronym GIMP (/ɡɪmp/ GHIMP), is a free and open-source raster graphics editor.

It is commonly used for photo retouching, image editing, free-hand drawing, and converting between different image file formats.

D-Bus (short for "Desktop Bus")is a message-oriented middleware mechanism that allows communication between multiple processes running concurrently on the same machine. D-Bus was developed as part of the freedesktop.org project, initiated by GNOME developer Havoc Pennington to standardize services provided by Linux desktop environments such as GNOME and KDE Plasma.

The freedesktop.org project also developed a free and open-source software library called libdbus, as a reference implementation of the specification. This library is not D-Bus itself, as other implementations of the D-Bus specification also exist, such as GDBus (GNOME), QtDBus (Qt/KDE), dbus-java and sd-bus (part of systemd).

The Quick Emulator (QEMU) is a free and open-source emulator that uses dynamic binary translation to emulate a computer's processor; that is, it translates the emulated binary codes to an equivalent binary format which is executed by the machine. It provides a variety of hardware and device models for the virtual machine, enabling it to run different guest operating systems. QEMU can be used with a Kernel-based Virtual Machine (KVM) to emulate hardware at near-native speeds. Additionally, it supports user-level processes, allowing applications compiled for one processor architecture to run on another.

QEMU supports the emulation of x86, ARM, PowerPC, RISC-V, and other architectures.