Atmospheric optics wavelengths. A halo (ἅλως; also known as a nimbus, icebow or gloriole) is an optical phenomenon produced by the interaction of light from the sun or moon with ice crystals in the atmosphere, resulting in colored or white arcs, rings or spots in the sky. Many halos are positioned near the sun or moon, but others are elsewhere and even in the opposite part of the sky. They can also form around artificial lights in very cold weather when ice crystals called diamond dust are floating in the nearby air. There are many types of ice halos. They are produced
Art of memory modern terminology, the concept that salient, bizarre, shocking, or simply unusual information will be more easily remembered can be referred to as the Von Restorff effect. The well-known role of repetition in the common process of memorization of course plays a role in the more complex techniques of the art of memory. The earliest of the references to the art of memory, the "Dialexis", mentioned above, makes this clear: "repeat again what you hear; for by often hearing and saying the same things, what you have learned comes complete into your memory." Similar advice is a commonplace in later works