Hiding and Showing Parallels Desktop
When you are working with Parallels Desktop, you can hide and show it and all its windows by pressing the F6 shortcut.
If Parallels Desktop is visible but running in the background, pressing F6 will bring Parallels Desktop and all its windows to focus.
Note 1: To be able to use the F6 shortcut, make sure the Enable Mac OS X system shortcuts option is enabled in the Keyboard pane of Parallels Desktop Preferences.
Note 2: F6 is the default shortcut for hiding/showing Parallels Desktop. You can set another shortcut for these actions in the Keyboard pane of Parallels Desktop Preferences.