Qt (framework)

Qt (framework)

Qt (/ˈkjuːt/ "cute", or unofficially as Q-T cue-tee) is a cross-platform application framework that is widely used for developing application software with a graphical user interface (GUI) (in which cases Qt is classified as a widget toolkit), and also used for developing non-GUI programs such as command-line tools and consoles for servers. Qt is most notably used in Autodesk Maya, The Foundry's Nuke, Adobe Photoshop Elements, Skype, VLC media player, VirtualBox, and Mathematica, and by the European Space Agency, DreamWorks, Google, HP, KDE, Lucasfilm, Panasonic, Philips, Samsung, Siemens, Volvo, Walt Disney Animation Studios and Research In Motion. The Opera web browser (up to version 10.0) also uses Qt, but only as an interface to the Linux platform.

Qt uses standard C++ but makes extensive use of a special code generator (called the Meta Object Compiler, or moc) together with several macros to enrich the language. Qt can also be used in several other programming languages via language bindings. It runs on the major desktop platforms and some of the mobile platforms. It has extensive internationalization support. Non-GUI features include SQL database access, XML parsing, thread management, network support, and a unified cross-platform application programming interface (API) for file handling.

Distributed under the terms of the GNU Lesser General Public License (among others), Qt is free and open source software. All editions support many compilers, including the GCC C++ compiler and the Visual Studio suite.

Qt is developed by an open source project, the Qt Project, involving developers as individuals and from firms working to advance Qt, such as Nokia, Digia, and others. Before the launch of the Qt Project, it was produced by Nokia's Qt Development Frameworks division, which came into being after Nokia's acquisition of the Norwegian company Trolltech, the original producer of Qt. In February 2011 Nokia announced its decision to drop Symbian technologies and base their future smartphones on Microsoft platform instead. One month later Nokia announced the sale of Qt's commercial licensing and professional services to Digia, although Nokia was to remain the main development force behind the framework at that time. On 9 May, it was announced on the Qt Labs website that the groundwork was being laid for the next major version of Qt, with the expectation that Qt 5 would be released in August 2012.

On 9 August 2012, Digia acquired Qt software technologies from Nokia. About 125 Qt developers will be transferred to Digia, with the immediate goal of bringing Qt support to Android, iOS and Windows 8 platforms.