1. Bridget Riley, Movement in Squares, 1961. OP ART
Op Art, also known as optical art, is a genre of visual art, especially painting, that makes use of optical illusions. Op art is also known as geometric abstraction and hard-edge abstraction, although the preferred term for it is perceptual abstraction.
"Optical Art is a method of painting concerning the interaction between illusion and picture plane, between understanding and seeing.“ Op art works are abstract, with many of the better known pieces made in only black and white. When the viewer looks at them, the impression is given of movement, hidden images, flashing and vibration, patterns, or alternatively, of swelling or warping.
Bridget Riley, Movement in Squares, OP ART

2. Bridget Riley, Movement in Squares, 1961. OP ART

3. Op Art is derived from the constructivist practices of the Bauhaus
Op Art is derived from the constructivist practices of the Bauhaus. This German school, founded by Walter Gropius, stressed the relationship of form and function within a framework of analysis and rationality. Students were taught to focus on the overall design, or entire composition, in order to present unified works. When the Bauhaus was forced to close in 1933, many of its instructors fled to the United States where the movement took root in Chicago, where Anni and Josef Albers would come to teach.
An optical illusion by Hungarian-born artist Victor Vasarely

4. Bridget Riley, Cataract 3, 1967. OP ART

5. Bridget Riley, Arrest 1, 1965. OP ART

6. Jenny Holzer
Jenny Holzer
As a graduate of Ohio University, the main focus of Jenny Holzer has been on the investigation of ways to disseminate ideas within public space. Since the late seventies, she has been working in the street and in public buildings, using media such as, LCD displays (e.g., in Times Square, New York) posters and stickers (applied to such urban elements as telephone booths or parking meters), these artworks art intended to stimulate awareness of our social conditioning as conveyed by the very landscape in which we may be confronted by them."

7. Jenny Holzer

8. Jenny Holzer

9. EXPRESSING ANGER IS NECESSARY LABOR IS A LIFE-DESTROYING ACTIVITY
Some of Jenny Holzer’s Truisms
EXPRESSING ANGER IS NECESSARY
LABOR IS A LIFE-DESTROYING ACTIVITY
DECENCY IS A RELATIVE THING
LEISURE TIME IS A GIGANTIC SMOKE SCREEN
IDEALS ARE REPLACED BY CONVENTIONAL GOALS AT A CERTAIN AGE
FEAR IS THE GREATEST INCAPACITATOR
THE WORLD OPERATES ACCORDING TO DISCOVERABLE LAWS
REVOLUTION BEGINS WITH CHANGES IN THE INDIVIDUAL
DISGUST IS THE APPROPRIATE RESPONSE TO MOST SITUATIONS
IT IS MAN'S FATE TO OUTSMART HIMSELF
IT'S VITAL TO LIVE IN HARMONY WITH NATURE
MONEY CREATES TASTE
MOSTLY YOU SHOULD MIND YOUR OWN BUSINESS
OLD FRIENDS ARE BETTER LEFT IN THE PAST
YOUR OLDEST FEARS ARE THE WORST ONES

10. Jenny Holzer

11. Earthworks
Earthworks
Land Art, Earthworks or Earth Art is an art movement which emerged in America in the late 1960s and early 1970s, in which landscape and the work of art are inextricably linked. Sculptures are not placed in the landscape, rather the landscape is the very means of their creation. The works frequently exist in the open, located well away from civilization, left to change and erosion under natural conditions.
Robert Smithson, Spiral Jetty, EARTHWORKS

12. Earthworks
Robert Smithson, 1969.

13. Unidentified, Marree Man (Stuart’s Giant) Discover June 26, 1998
Earthworks
Unidentified, Marree Man (Stuart’s Giant) Discover June 26, 1998
EARTHWORKS

14. Walter De Maria, The Lightning Field, 1977. EARTHWORKS

15. Nancy Holt, Sun Tunnels, 1973-76. EARTHWORKS
Four cast concrete, 18 ft. tunnels with open ends aligned with the points on the horizon where the sun rises and sets at the winter and summer solstices. Penetrating the tunnels are holes with diameters of 7 to 10 inches in the patterns of the four constellations of; Capricorn, Draco, Columbia and Perseus.

16. Nancy Holt, Sun Tunnels, 1973-76. EARTHWORKS

17. Earthworks