Hide/show components

I recently watched a YouTube video, "How to show what you want - Solidworks assembly drawing section"' and at 00:35 the instructor hides parts by selecting them with the cursor. Although his movement is rapid, at no point does he access the feature tree or any other menu. He also makes the parts reappear without using any menus. How does he do this?

SolidworksDrawings And Detailing