Though it's a simple little experiment, the result is unexplained. Benham's top (also known as Benham's disk) is toy that was sold in 1895 with a specific black and white pattern painted on it. When the top spins, many people see colors in the rings. Not everyone sees the colors; and for those who do see colors, not everyone sees the same ones. There is no definitive explanation for this optical illusion phenomenon. The pale colors perceived when the disk spins are called Fechner colors, or pattern-induced flicker colors (PIFCs). The toy was named after its English maker, Charles Benham.