A silkscreen, also called a serigraphy, is a stencil print.

The printmaker cuts an image in a sheet of paper or plastic film.
The printmaker removes the cutaway areas, creating a stencil. The open spaces in the stencil are the shapes that will print.
The stencil is placed on a screen made of silk or other thin cloth, stretched on a frame.
A piece of paper is placed under the frame. The printmaker pulls a thin rubber blade (a squeegee) across the screen. This squeezes ink through the open areas of the screen onto the paper underneath in the other areas, the ink is blocked.
When the screen is raised, the image has been printed on the paper. It is not in reverse.