Screen printing, also known as silk screening, is a printing technique that involves using a mesh screen to transfer ink onto a substrate, except in areas blocked by a stencil. The process begins with creating a stencil, usually made of photo emulsion or film, which is then attached to the mesh screen. The screen is placed over the substrate, typically fabric, paper, or plastic, and a dollop of ink is applied to the top of the screen. A squeegee is then used to spread the ink across the screen, forcing it through the fine mesh openings and onto the substrate in the pattern dictated by the stencil. Once the ink is applied, the substrate is heated to cure the ink and produce a durable, long-lasting print. Screen printing is widely used for printing on t-shirts, posters, signage, and other promotional items due to its ability to produce vibrant, long-lasting colors and precise designs.