Waters, "The phrase [parlor magic] is often used as a pejorative to imply that an effect under discussion is not suitable for professional performance.
The balls in the illusion are typically brightly colored, while the cups are usually opaque. In parlor magic, the performer is usually standing and on the same level as the audience, which may be seated on chairs or even on the floor.
The great escapologist and illusionist Harry Houdini devoted much of his time to exposing such fraudulent operators. Less fraught with controversy, however, may be the use of deceptive practices by those who employ conjuring techniques for personal gain outside the venue of a magic performance.
Visual and cognitive illusions Visual illusions occur when the physical circumstances outside our mind deceive us. Say Cheese is a magic trick that uses this principle to perform a magic trick.
Many books have been written about magic tricks; so many are written every year that at least one magic author  has suggested that more books are written about magic than any other performing art. The Hobgoblin of Marvel Comics possesses "psy-powers" that enable him to create entire demonic realms.
During the 17th century, many books were published that described magic tricks. This book describes the history of this illusion both from a scientific perspective and its performance history as a magic trick.