Fashion design is a form of art that involves creating clothing designs. Modern fashion design is divided into haute couture and ready-to-wear categories. Haute couture involves custom designs for specific customers, while ready-to-wear designs are mass produced in standard sizes. Charles Frederick Worth was the first fashion designer in the 19th century, establishing the first fashion house in Paris and dictating styles to customers rather than following royal fashion. In the 1940s, clothing styles were limited by wartime shortages, but women began wearing trousers for practicality and uniforms became trendy even for non-military events.