In a nutshell:
Coined by Time Magazine in 1964, ‘Op-Art’ is short for ‘optical art’ as it relates to the human optical system and usually uses forms of optical illusions, or tricks of the eye. With influences from Neo-impressionism, Cubism, Futurism and Constructivism, Op-Art is usually, but not exclusively, in black and white with high contrast, hatching and repeated patterns. This style of pattern lends its self to optical illusions.
A bit more:
Remember when you were a kid being fascinated the first time you saw an optical illusion? It appeals to your sense of awe, your sense of what you think you know vs what you are seeing. In short.. it makes you think!
Optical illusions, by their nature, tap into our sense of reality. This is a powerful thing for a picture or an animation to be able to do. This is also why this type of artwork, although going through stages of popularity, seems to have a universal appeal and is relevant for such a diverse audience. In a cluttered and (some might argue) superficial modern world, artists and designers are looking to tap into more basic human instincts.
For some beautiful Op-Art inspired women by artist Adam Pizurny check out www.twenty75.com/projects/black-and-white-by-adam-pizurny/
More recent movements: