Silkscreen printing is a stencil technique that’s been around for centuries. A rubber bladed squeegee (probably not used centuries ago) is used to force ink through the open areas of a fabric screen onto a piece of paper. Each color requires a separate screen and each screen has to be aligned perfectly for proper registration. The whole squeegee, screen and ink process is repeated for each color on a card with time allowed in between for the ink to dry. Look at your favorite card and count the colors, then you’ll know how many screens were used to make it.