#6 GOBO -- means “goes before optics”. "Cookie" Gobos can be anything that is positioned between your flash & your subject. Shadow patterns are produced from the light passing through the "cookie" as well as the subject. Used to create captivating light & shadow patterns for making the backdrop of a portrait more lively. "Flag" Gobos are used to block light from hitting a particular portion of your subject. These are generally rectangular in form and opaque.