GTK+ is a multi-platform toolkit for creating graphical user interfaces. Offering a complete set of widgets, GTK+ is suitable for projects ranging from small one-off projects to complete application suites.
GTK+ has been designed from the ground up to support a range of languages, not only C/C++. Using GTK+ from languages such as Perl and Python (especially in combination with the Glade GUI builder) provides an effective method of rapid application development.
Qt is a cross-platform application and UI framework. Using Qt, you can write applications once and deploy them across many desktop and embedded operating systems without rewriting the source code.
Google Web Toolkit (GWT) is an open source Java software development framework that makes writing AJAX applications like Google Maps and Gmail easy for developers who don't speak browser quirks as a second language. Writing dynamic web applications today is a tedious and error-prone process; you spend 90% of your time working around subtle incompatibilities between web browsers and platforms.
wxWidgets lets developers create applications for Win32, Mac OS X, GTK+, X11, Motif, WinCE, and more using one codebase. It can be used from languages such as C++, Python, Perl, and C#/.NET. Unlike other cross-platform toolkits, wxWidgets applications look and feel native. This is because wxWidgets uses the platform's own native controls rather than emulating them.
Dojo builds on a fast, lightweight base that provides a competitive set of features (DOM traversal, AJAX, animations, event handling) at the same size as many of the alternative "lightweight" toolkits.
On top of that base Dojo provides easy access to an extensive collection of optional modules, including a widget framework that focuses on accessibility a...
wxPython is a Python extension module that wraps the wxWidgets cross-platform GUI library and provides an alternative to Tkinter and PythonWin. It attempts to mirror the class hierarchy of wxWidgets as closely as possible and is very versatile. It can be used to create standalone GUI applications or can be used in situations in which Python is embedded in a wxWidgets C++ application as an internal scripting or macro language. The currently supported GUIs are Win32, GTK/X-Windows, and Mac OS X.
The ADAPTIVE Communication Environment (ACE) is a freely available, open-source object-oriented (OO) framework that implements many core patterns for concurrent communication software. ACE provides a rich set of reusable C++ wrapper facades and framework components that perform common communication software tasks across a range of OS platforms.
Umbrella project for integrations of Wicket and other projects such as Jasper Reports, Hibernate, Freemarker. Also a home for small community contributions.
GeoTools is an open source (LGPL) Java code library which provides standards compliant methods for the manipulation of geospatial data, for example to implement Geographic Information Systems (GIS). The GeoTools library implements Open Geospatial Consortium (OGC) specifications as they are developed, in close collaboration with the GeoAPI and GeoWidgets projects.
The Visualization ToolKit (VTK) is an open source, freely available software system for 3D computer graphics, image processing, and visualization used by thousands of researchers and developers around the world. VTK consists of a C++ class library, and several interpreted interface layers including Tcl/Tk, Java, and Python. Professional support and products for VTK are provided by Kitware, Inc.
Ajax with style.
Framework that enables ajax on web pages with kss (css-like resources).
No need of Javacript knowledge to use it.
Included in Plone since 3.0
It includes a platform-independent development tool chain, a state-of-the-art GUI toolkit and an advanced client-server communication layer. It is Open Source under an LGPL/EPL dual license.
Insight Segmentation and Registration Toolkit (ITK) is an open-source software system to support the Visible Human Project. Currently under active development, ITK employs leading-edge segmentation and registration algorithms in two, three, and more dimensions.
NLTK — the Natural Language Toolkit — is a suite of open source Python modules, linguistic data and documentation for research and development in natural language processing, supporting dozens of NLP tasks, with distributions for Windows, Mac OSX and Linux.
SWT is an open source widget toolkit for Java designed to provide efficient, portable access to the user-interface facilities of the operating systems on which it is implemented.