Jackson Pollock, Willem de Kooning, Mark Rothko, and Arshile Gorky are all considered pioneers of Abstract Expressionism.

Abstract Expressionism is characterized by an emphasis on emotional expression, the use of abstract forms and colors, and the rejection of traditional techniques and materials.

Dripping, pouring, collage, and assemblage are all techniques commonly used in Abstract Expressionism.

Jackson Pollock's famous drip painting technique is called dripping.

Mark Rothko is known for his large-scale abstract paintings with bold colors.

Willem de Kooning's famous painting that depicts a woman with a distorted face is called Woman I.

Arshile Gorky is known for his biomorphic forms.

Pop Art, Minimalism, and Conceptual Art all emerged in the 1940s and 1950s as a reaction against Abstract Expressionism.

Andy Warhol, Roy Lichtenstein, Keith Haring, and Jean-Michel Basquiat are all considered pioneers of Pop Art.

Pop Art is characterized by the use of popular culture imagery, bright colors and bold forms, and mass production and repetition.

Donald Judd, Carl Andre, and Dan Flavin are all known for their minimalist sculptures.

Minimalism is characterized by simplicity of form, the use of industrial materials, and repetition and seriality.

Joseph Kosuth, Sol LeWitt, and Lawrence Weiner are all known for their conceptual art installations.

Conceptual Art is characterized by an emphasis on the idea or concept behind the work, the use of non-traditional materials and techniques, and the rejection of traditional notions of art.

Jackson Pollock, Willem de Kooning, Mark Rothko, and Arshile Gorky are all considered pioneers of Abstract Expressionism.