Convex mirrors are often used as security mirrors to help protect easily stolen items; for instance, in retail establishments. Concave mirrors are most commonly used in light sources such as car side mirrors.
Convex mirrors bulge outwards or towards the object they are reflecting. Concave mirrors curve inwards or away from the object they are reflecting.
Convex and concave mirrors both distort images; however, they have different effects. Convex mirrors magnify images and cause light to diverge. Concave mirrors shorten images and focus light into parallel beams.
Convex and concave mirrors have one feature in common: they are made from a substrate with a reflective coating. Modern mirrors use a silver nitrate reflective coating applied to back of the substrate that is as thin as paper and protected by a silicone-based paint. Glass is the most commonly used substrate due to its rigidity and transparency, according to MirrorLink.org.
Both convex and concave mirrors are used in fun houses and are often combined to create distorted reflections.