Screenshot of KDE:
KDE is probably the second most well-known DE available after GNOME-Shell and is a Qt-based desktop environment
The range of options is just incredible. It can use a traditional task bar, a unity-like dock, any number of panels.
Very easily modifiable
If you were looking for a wallpaper, a widget, ect... If you would go under System Settings and press the "Get more" button, a dialog will pop up and all that you need to do is press the "install" button, that it.
They can be used on the desktop or in the panel.
A way to organize your workspaces based on activities.
┃ │ Required │ Recommended ┃
┃ Processor │ 1 GHz (x86) │ Better than 1 GHz (x86)┃
┃ Memory │ 512 MB │ 1 GB ┃
┃ Hard drive capacity │ 4 GB │ 10 GB ┃
┃ Video card │ VGA @ 640×480 │ VGA @ 1024×768 ┃
Note: If "Desktop effects" are desired, a supported GPU is required.
How to install
But it is recommended to install it from the official image (.iso) that can be downloaded at this page.