What is desktop? What is taskbar?

Desktop:  The desktop is the primary user interface of a computer Operating System.   It is the
background image of a display screen, on which windows, icons of files, folders and other graphical
items appear in the graphical user interfaces. Icons on a computer desktop can be arranged like the
real objects on a real desktop.

Taskbar: The taskbar is a movable, concealable icon bar that is set on the very edge of the graphical
user interface (GUI) desktop and serves as a launching pad for applications as well as a holder for
icons indicating running programs