Optical toys are a type of toy that use light and mirrors to create interesting visual effects. The most popular optical toy is the kaleidoscope, which uses mirrors and colored pieces of glass to create a symmetrical pattern. The zoetrope is another optical toy that creates the illusion of motion when viewed through its slits. Lastly, the phenakistoscope is an optical toy that uses a spinning disc with images on it to create the illusion of motion. All three of these optical toys provide hours of entertainment and are a great way to explore the science of light and optics.