KDE Plasma (formerly K Desktop Environment and KDE Software Compilation and KDE Plasma Workspace and Applications) is an open source project comprised of numerous packages, libraries and applications designed to provide a modern graphical desktop environment for Linux and UNIX-like workstations.
A beautiful, modern and traditional desktop environment
It combines ease-of-use, superior graphical design and powerful functionality with the unique features and architecture of the Linux operating system. It’s comprised of the KDE Plasma Workspaces and KDE Applications components.
Additionally, it contains extra add-on for the panel and desktop, a download manager, an instant messenger, an addressbook, a document viewer, a multimedia layer called Phonon (similar to GStreamer on GNOME), and accessibility functionality, such as a powerful text-to-speech system.
Numerous GNU/Linux distributions use KDE
Numerous modern Linux distributions are built around the KDE desktop environment, either using it as their main computing environment or as an alternate one. Just like in the GNOME desktop environment, KDE tries to keep the same look and feel across all of its default applications. The entire KDE project is written with the Qt toolkit.
Under the hood
Under the hood, the KDE Plasma project is comprised of many core libraries that form KDE Frameworks and are required by all applications, various runtime components that ensure the proper functionality of the included apps, the applications, and the actual user environment.
Comes pre-loaded with apps for daily tasks
Users will find at least one application for each common task, including emailing, web browsing, news reading, painting, image viewing, video and music playback, and many more.
It also includes a collection of basic utilities, such as a calculator or archive manager, various scientific and educational applications, packages that contain extra themes, icons, wallpapers, window decorations and screensavers, some system administration tools, bindings for well known programming languages, and many games.
It is one of the first and best desktop environments for Linux distributions. During the last couple of years, KDE proved to be a very mature, reliable and stable project, backed by a talented community.