Art Nouveau is a design movement that emerged in Europe during the 19th and 20th centuries, aiming to modernize design by challenging traditional hierarchies and emphasizing craftsmanship. It features organic and geometric forms to create elegant designs, advocating that an object's function should dictate its form. Hector Guimard, a prominent architect of this style, has gained recognition for his significant contributions to Art Nouveau architecture and design, particularly through works like the Castel Béranger and Paris Metro.