Back in the 80's windowed environments were brand new so most people needed a little help in understanding how everything worked.
So, soon after the ST's release in July of 1985, Atari released a demo to help people understand how to interact with their new-fangled windowed operating system. Of course, the demo didn't have a lot of fancy graphics or voice instructions. It was just a simple walkthrough that allowed users to interact with demo, showing how to use the mouse to click on desktop menus, file managers and various other windows.
Makes you realize how good we have it now.
For complete instructions and a walkthrough
watch the video below