Shell components are the fundamental parts of an operating system's user interface that allow users to interact with files, folders, menus, and the desktop environment. In Windows, these components include elements like the taskbar, Start menu, file explorer, and desktop icons. They provide a graphical or command-line interface, making it easier for users to access applications, manage files, and customize their workspace. Shell components are essential for navigating and controlling the computer without needing to understand complex system commands.