|The Mirror of Galadriel in The Lord of the Rings|
Scrying is another form of divination you have likely witnessed in movies and maybe even in real life, but you just don't know that term for it. It was part of the events that lead up to the Salem Witch Trials that are so famous.
So what is scrying?
It's basically the practice of looking into an object to divine the future or to witness spiritual visions. The object can be any number of things like a translucent rock, pool of water, crystal, etc. The person stares into the object often for long periods of time until they start to see words, objects or even cinematic events play out before their eyes. You likely have seen movies where an old gypsy stares into a crystal ball and things appear to her -- that is a form of scrying. Another movie example of scrying is Galadriel's mirror as portrayed in The Fellowship of the Rings.
Those who believe in scrying claim that the object used for the practice actually helps focus a psychic's sixth sense. There are people who claim that through scrying they can see not only the future, but present events and even the past. Some parapsychologists even claim that they have been able to confirm the validity of scrying in a laboratory setting, but such claims have not been substantiated by the scientific community at large.
In the Salem Witch Trials it came out that the slave of one of the girl's families engaged in scrying with the girls by cracking a raw egg into a glass of water. It's an old Voodoo practice, with the egg white forming different objects as it swirls in the water, providing insight to those who stare at it long enough.
You can even argue that games like Bloody Mary, where you stare into a mirror in a darkened room and repeat her name rapidly, is a form of scrying. Even Snow White's evil stepmother engages in the practice of scrying.