There are many myths and urban legends surrounding a simple household mirror. For example, it's generally believed that when you accidentally break a mirror, it would grant you seven years bad luck. It is believed that the origin for this myth stems from the fact that, at the time, a mirror not only reflected your physical appearance in its glass, but it was also believed that a mirror would manifest a reflection of your soul in its glass. If one were to accidentally break a mirror, it also broke your soul. At times, if one's soul was broken by a mirror cracking, then that person would be exposed to all the misfortune that comes with living, because that person wouldn't have a soul that would protect him or her from the chaos.
Another myth involves applying your hand to a bathroom mirror in your house. If you held your hand in that position long enough, you would feel a strange sensation in your finger tips. This meant that there was something lurking in your mirror, and it would be best if you removed your hand from that position so that you're hand wouldn't be attacked. It's also believed that people inhabit the mirror and study your every movement. These people are jealous of your life, and they would do anything in their power to switch places with you.
There's also the famous Bloody Mary, the supposed ghost of a deceased witch that is said to appear in one's bathroom mirror. As the story goes, a person would go into his or her bathroom and proceed to close the door and turn off the bathroom lights. They would then look into the mirror and say "Bloody Mary" three or thirteen times, depending on the version you're hearing. The ghost of Bloody Mary is then supposed to appear in your mirror. What happens after she is summoned varies. She would either kill you on the spot, gouge your eyes out, or she may even pull you into the mirror with her, and you will be trapped in there for eternity. It's also believed that you can summon other specters into your home by using a mirror. Other examples of this type of summoning includes the Candyman from the Candyman horror series, and Baby Blue, a recently new urban legend regarding a deceased baby.