- Light travels in straight lines at very high speeds and we see objects because light reflects off their surfaces into our eyes. Shadows are formed when light is blocked. - Reflection is when light bounces off a surface at the same angle it hits the surface. White light is made of all the colors of the rainbow, which can be separated and recombined. - Refraction occurs when light changes speed in different mediums like air and water, causing bending of light rays. The color something appears depends on the colors of light it reflects.