Abstract expressionism emerged in New York City in the 1940s as a spontaneous style of painting that focused on the emotional experience rather than depicting objects or images. Key figures like Jackson Pollock and Willem de Kooning developed techniques like Pollock's drip method that emphasized fluid paint application. By the 1950s, abstract expressionism had spread to other American cities and to Paris, influencing architecture and other fields by embracing non-representational forms that conveyed personal feelings. It marked a shift away from social realism and toward abstraction, though its roots were varied, involving influences from surrealism and Russian artist Wassily Kandinsky.