If your Mac is anything like mine, you end up with lots of apps open, each with one or more windows that obscure the Desktop. For those people who like to save in-progress documents to the Desktop and keep current project folders there, all those windows get in the way. macOS has a solution. Open System Preferences > Mission Control, and in the Keyboard and Mouse Shortcuts section, from the Show Desktop pop-up menu, choose a keyboard shortcut. You can also click the “Hot Corners” button and do it with a mouse movement. My personal favorite is to set my upper right corner to activate the Desktop. I just move my mouse all the way into the corner and all of the windows fly away revealing my desktop. Another move into the corner and they all fly back into position.
You can even do this while dragging and dropping. Pick up a file from Finder, activate your shortcut that you set while still holding the file with your mouse, and then dop the file onto the desktop right where you want it.