Solar control and Privacy films are for use on glass to help give privacy or the glare of the sun. Solar control films come in either silver or bronze and give a mirror effect. The side with the brightest light is like a mirror. During the day the outside would be the mirror so you cannot see in, but at night with light on the inside would be the mirror and people outside would be able to see in.
Privacy film stop people from seeing in but allow the light through. If you put your hand against it you can see, but as you move it away the image goes blurred so people cannot see. Blackout film this is used to block light coming in the room at all.