One of the features that sets KDE apart from other desktop environments is the concept of Plasmoids. Plasmoids are a suite of applets that can be added to your desktop in order to show useful information, provide a service, or perhaps give you something neat to look at. For example, you can add a Plasmoid to control a media player, display a comic strip on the screen, weather information, statuses from social networking accounts, and the list goes on.
To add a new Plasmoid, right-click on an empty portion of the desktop and then click on Add widgets. Along the bottom of your screen, a horizontal list of available widgets will be displayed. To add one, drag it onto your desktop. To remove it, hover your mouse pointer over one and click on the x icon that appears in the pop-up menu. The following screenshot shows KDE's menu to add widgets:
In fact, the entire desktop itself is a Plasmoid, known as a Layout. In Mint, KDE's layout is set as Folder, which is a layout that closely resembles classic desktop paradigms. For example, with Mint's default Folder layout, you can add shortcut icons, folders, and files to your desktop. However, this is not the norm in KDE. By default, KDE normally opts for the Desktop layout, which doesn't feature icons at all and is just a canvas for you to place Plasmoids. To select a different layout for your desktop, right-click anywhere on the desktop where there is no icon or Plasmoid and click on Folder settings. In the window that appears, you can select a different layout. Feel free to test out the various layouts available to see which ones you like best.
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You can also add a Plasmoid to your panel. To do so, simply drag a Plasmoid onto your panel rather than onto your desktop.
One Plasmoid that is especially useful is Folder. The Folder Plasmoid displays the contents of a single folder, which is very useful if there is a specific folder you access frequently, such as your home directory. Some users place a Folder Plasmoid onto their desktop to provide the same functionality of the Folder layout, but constrained to a specific area. This allows one to use the Desktop layout but still benefit from desktop icons. The following screenshot shows KDE's Folder Plasmoid:
By utilizing the various layouts as well as Plasmoids, you're able to create a desktop design that is truly your own, with all of the items that you find most relevant to the way in which you use your computer available to you. The possibilities are endless, so feel free to experiment.