GTK, which stands for the Gimp ToolKit, is a library for creating graphical user interfaces. It is designed to be small and efficient, but still flexible enough to allow the programmer freedom in the interfaces created. GTK provides some unique features over standard widget libraries.
For users on Linux and Unix, KDE offers a full suite of user workspace applications which allow interaction with these operating systems in a modern, graphical user interface. This includes Plasma Desktop, KDE's innovative and powerful desktop interface. Other workspace applications are included to aid with system configuration, running programs, or interacting with hardware devices. While the fully integrated KDE Workspaces are only available on Linux and Unix, some of these features are available on other platforms. In addition to the workspace, KDE produces a number of key applications such as the Konqueror Web browser, Dolphin file manager, and Kontact, the comprehensive personal information management suite. The list of applications includes many others, including those for education, multimedia, office productivity, networking, games, and much more. Most applications are available on all platforms supported by the KDE Development. KDE also brings to the forefront many innovations for application developers. An entire infrastructure has been designed and implemented to help programmers create robust and comprehensive applications in the most efficient manner, eliminating the complexity and tediousness of creating highly functional applications.
Qt is a comprehensive, object-oriented development framework that enables development of high-performance, cross-platform rich-client and server-side applications. When you implement a program with Qt, you can run it on the X Window System (Unix/X11), Apple Mac OS X, and Microsoft Windows NT/9x/2000/XP by simply compiling the source code for the platform you want. Qt is the basis for the KDE desktop environment, and is also used in numerous commercial applications such as Google Earth, Skype for Linux, and Adobe Photoshop Elements.
NoMachine NX is a fast terminal server and desktop virtualization system based on the X11 protocol. NX is an order of magnitude faster than VNC or X11 and can run on bandwidth as narrow as 10 kBit/sec. In addition, NX translates and embeds the MS Windows Terminal Server and VNC protocols into X/NX, enabling users to compress and accelerate remote Windows and VNC sessions. The NX project provides a suite of libraries and X11 proxying agents implementing efficient compression and optimized transport of X11, SMB, IPP, HTTP, and arbitrary protocols like audio and video over the Internet.
Eric is a full featured Python and Ruby editor and IDE, written in Python. It is based on the cross platform Qt GUI toolkit, integrating the highly flexible Scintilla editor control. It is designed to be usable as an everyday quick and dirty editor as well as being usable as a professional project management tool, integrating many advanced features that Python offers the professional coder. Eric includes a plug-in system, which allows easy extension of the IDE functionality with plug-ins downloadable from the net. Current stable versions are Eric4 based on Qt4 and Python 2 and Eric5 based on Python 3 and Qt4.
CUPS is a standards-based printing system for Mac OS X and other Unix-like operating systems. It provides the System V and Berkeley command line interfaces, and uses the Internet Printing Protocol ("IPP") as the basis for managing print jobs and queues. The Line Printer Daemon (LPD) Server Message Block (SMB), and AppSocket (a.k.a. JetDirect) protocols are also supported with reduced functionality. CUPS adds network printer browsing and PostScript Printer Description ("PPD") based printing options to support real world printing.
Wine is an implementation of the Windows API on top of X and Unix. It does not require Microsoft Windows, but can use native Windows DLLs if they are available. It provides both a development toolkit for porting Windows source code to Unix as well as a program loader, allowing many unmodified Windows programs to run on x86-based Unixes.
Tulip is an information visualization framework dedicated to the analysis and visualization of relational data. Tulip aims to provide the developer with a complete library, supporting the design of interactive information visualization applications for relational data that can be tailored to the problems being faced. Written in C++, the framework enables the development of algorithms, visual encodings, interaction techniques, data models, and domain-specific visualizations. One of the goals of Tulip is to facilitate the reuse of components, and it allows developers to focus on programming their application. This development pipeline makes the framework efficient for research prototyping as well as the development of end-user applications. The framework also provides a complete software for visual analysis of relational data having attributes.
Ghostscript is a processor for PostScript and PDF files. It can rasterize these files to a wide variety of printers, devices for screen preview, and image file formats. Since applications tend to prepare pages for printing in a high-level format such as PostScript, most Unix users with low-level bitmap printers, such as inkjets, use GhostScript as part of the printing process. In addition, Ghostscript is capable of converting PostScript files, functionality comparable to Adobe Acrobat Distiller, but on the command line. In addition, Ghostscript is used for file import and viewing by a great many other applications, including xv, ImageMagick, gimp, and xdvi. Several GUI wrappers for viewing PostScript and PDF files exist, including GSview, ghostview, gv, ggv, and kghostview. This is far from a comprehensive list.