Screen printing utilizes different types of brightly colored inks and is often used for printing posters, t-shirts and other promotional items. Initially, screen printing was confined on silk materials. Nowadays, several different types of materials are used. During the screen printing process, a design is laid on the top of the screen. Thereafter, it is covered with photo emulsion and exposed to light. Due to its exposure to heat, the emulsion hardens up and the rest of it is washed away by leaving one kind of a stencil whose ink can be pulled by using a squeegee.