The document provides an overview of Impressionism from 1874-1890s. It discusses key Impressionist artists like Monet, Renoir, Degas, and their techniques of capturing light and fleeting moments in plein air works. It also summarizes the societal changes of industrialization and new scientific theories that influenced Modernism's shift towards critiquing artistic conventions. Post-Impressionism emerged in the 1880s-1890s as artists built upon Impressionism towards greater structure, color theory, and abstraction.