Scrying is a form of divination where the diviner induces visions. These visions can be induced by using a multitude of things such as mirrors, crystal balls, flames, water, and many others.
It is unknown where exactly this method of divination originated. There are records of scrying going as far back as the 10th century. It is believed that the things seen while scrying are either from the subconscious or from otherworldly beings.
For using any of these methods, it is best to meditate and enter a trance-like state.
Due to our media, this is one of the most well known types of scying. The use of a crystal ball is very popular for this method of divination.
This method is commonly done by pouring water into a black or dark colored bowl and gazing at the surface of the water.