KDE Plasma is an open-source desktop environment created by the KDE free software community. It is designed to provide a modern and user-friendly interface for users of Linux, BSD, and other Unix-like operating systems. It consists of a graphical user interface (GUI) for interacting with the computer, along with a wide range of application and utilities for managing files, networking, and multimedia. KDE Plasma includes a range of features such as a customizable workspace, a taskbar, window management, and a variety of applications. It also includes a wide range of widgets and themes, allowing users to customize the look and feel of their desktop environment. KDE Plasma is also highly configurable and extensible, allowing users to customize and extend the features of their desktop environment. Finally, it is highly secure and stable, allowing users to run their applications without fear of crashes or malware.
Xfce is good because it is fast, light and has almost all the features of Plasma.