The Harmony toolkit is a never-completed free software widget toolkit that aimed to be API compatible with the then non-GPL licensed Qt widget toolkit. The QPL license that Qt used was free only if the program was not sold for profit and if its source code was freely available. It was later released under the terms of the GNU Lesser General Public License (LGPL).
In addition to source compatibility with Qt, the Harmony project also aimed to add functionality such as multi-threaded applications and pluggable themes, features that Qt itself later added.
The GNU Project launched the Harmony project, and also the GNOME desktop project, to counter the perceived problem that the free software KDE desktop was gaining popularity but was requiring that people install non GPL licensed software. In July 1997 the GNU Project called for volunteers for a Qt replacement in GNU's Bulletin [1] and listed it as a top priority task on its website. [2]
Development ceased at the end of 2000, when Qt was released under the GPL, removing the perceived need for the Harmony Project to exist. In January 2009 Qt itself was made available under the GNU LGPL, along with the previous license options.
The Common Desktop Environment (CDE) is a desktop environment for Unix and OpenVMS, based on the Motif widget toolkit. It was part of the UNIX 98 Workstation Product Standard, and was for a long time the Unix desktop associated with commercial Unix workstations. It helped to influence early implementations of successor projects such as KDE and GNOME desktop environment, which largely replaced CDE following the turn of the century.
The GNU Lesser General Public License (LGPL) is a free-software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate a software component released under the LGPL into their own software without being required by the terms of a strong copyleft license to release the source code of their own components. However, any developer who modifies an LGPL-covered component is required to make their modified version available under the same LGPL license. For proprietary software, code under the LGPL is usually used in the form of a shared library, so that there is a clear separation between the proprietary and LGPL components. The LGPL is primarily used for software libraries, although it is also used by some stand-alone applications.
Qt is free and open-source cross-platform software for creating graphical user interfaces as well as cross-platform applications that run on various software and hardware platforms such as Linux, Windows, macOS, Android or embedded systems with little or no change in the underlying codebase while still being a native application with native capabilities and speed.
The Q Public License (QPL) is a non-copyleft license, created by Trolltech for its free edition of the Qt. It was used until Qt 3.0, as Trolltech toolkit version 4.0 was released under GPL version 2.
In computing, Motif refers to both a graphical user interface (GUI) specification and the widget toolkit for building applications that follow that specification under the X Window System on Unix and Unix-like operating systems. The Motif look and feel is distinguished by its use of rudimentary square and chiseled three-dimensional effects for its various user interface elements.
wxWidgets is a widget toolkit and tools library for creating graphical user interfaces (GUIs) for cross-platform applications. wxWidgets enables a program's GUI code to compile and run on several computer platforms with minimal or no code changes. A wide choice of compilers and other tools to use with wxWidgets facilitates development of sophisticated applications. wxWidgets supports a comprehensive range of popular operating systems and graphical libraries, both proprietary and free, and is widely deployed in prominent organizations.
The GNU Project is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and computing devices by collaboratively developing and publishing software that gives everyone the rights to freely run the software, copy and distribute it, study it, and modify it. GNU software grants these rights in its license.
Fast Light Toolkit is a cross-platform widget library for graphical user interfaces (GUIs), developed by Bill Spitzak and others. Made to accommodate 3D graphics programming, it has an interface to OpenGL, but it is also suitable for general GUI programming.
PyQt is a Python binding of the cross-platform GUI toolkit Qt, implemented as a Python plug-in. PyQt is free software developed by the British firm Riverbank Computing. It is available under similar terms to Qt versions older than 4.5; this means a variety of licenses including GNU General Public License (GPL) and commercial license, but not the GNU Lesser General Public License (LGPL). PyQt supports Microsoft Windows as well as various flavours of UNIX, including Linux and MacOS.
PyGTK is a set of Python wrappers for the GTK graphical user interface library. PyGTK is free software and licensed under the LGPL. It is analogous to PyQt/PySide and wxPython, the Python wrappers for Qt and wxWidgets, respectively. Its original author is GNOME developer James Henstridge. There are six people in the core development team, with various other people who have submitted patches and bug reports. PyGTK has been selected as the environment of choice for applications running on One Laptop Per Child systems.
Assistive Technology Service Provider Interface (AT-SPI) is a platform-neutral framework for providing bi-directional communication between assistive technologies (AT) and applications. It is the de facto standard for providing accessibility to free and open desktops, like Linux or OpenBSD, led by the GNOME Project.
Linux 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, which includes the kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name "GNU/Linux" to emphasize the importance of GNU software, causing some controversy.
In the 1950s and 1960s, computer operating software and compilers were delivered as a part of hardware purchases without separate fees. At the time, source code, the human-readable form of software, was generally distributed with the software providing the ability to fix bugs or add new functions. Universities were early adopters of computing technology. Many of the modifications developed by universities were openly shared, in keeping with the academic principles of sharing knowledge, and organizations sprung up to facilitate sharing. As large-scale operating systems matured, fewer organizations allowed modifications to the operating software, and eventually such operating systems were closed to modification. However, utilities and other added-function applications are still shared and new organizations have been formed to promote the sharing of software.
The GNU General Public License is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general use and was originally written by the founder of the Free Software Foundation (FSF), Richard Stallman, for the GNU Project. The license grants the recipients of a computer program the rights of the Free Software Definition. These GPL series are all copyleft licenses, which means that any derivative work must be distributed under the same or equivalent license terms. It is more restrictive than the Lesser General Public License and even further distinct from the more widely used permissive software licenses BSD, MIT, and Apache.
GNOME, originally an acronym for GNU Network Object Model Environment, is a free and open-source desktop environment for Linux and other Unix-like operating systems.
The KDE Software Compilation was an umbrella term for the desktop environment plus a range of included applications produced by KDE. From its 1.0 release in July 1998 until the release of version 4.4 in February 2010, the Software Compilation was simply known as KDE, which stood for K Desktop Environment until the rebrand. The then called KDE SC was used from 4.4 onward until the final release 4.14 in July 2014. It consisted of the KDE Plasma 4 desktop and those KDE applications, whose development teams chose to follow the Software Compilation's release schedule. After that, the KDE SC was split into three separate product entities: KDE Plasma, KDE Frameworks and KDE Applications, each with their own independent release schedules.
mpv is free and open-source media player software based on MPlayer, mplayer2 and FFmpeg. It runs on several operating systems, including Unix-like operating systems and Microsoft Windows, along with having an Android port called mpv-android. It is cross-platform, running on ARM, PowerPC, x86/IA-32, x86-64, and MIPS architecture.
KDE Projects are projects maintained by the KDE community, a group of people developing and advocating free software for everyday use, for example KDE Plasma and KDE Frameworks or applications such as Amarok, Krita or Digikam. There are also non-coding projects like designing the Breeze desktop theme and iconset, which is coordinated by KDE's Visual Design Group. Even non-Qt applications like GCompris, which started as a GTK-based application, or web-based projects like WikiToLearn are officially part of KDE.
GNOME 1 is the first major release of the GNOME desktop environment. Its primary goal was to provide a consistent user-friendly environment in conjunction with the X Window System. It was also a modern and free and open source software alternative to older desktop environments such as the Common Desktop Environment (CDE), but also to the K Desktop Environment (KDE). Each desktop environment was built-upon then proprietary-licensed widget toolkits, whereas GNOME's goal from the onset, was to be freely-licensed, and utilize the GTK toolkit instead.