Vittorio De Sica was an influential Italian film director, actor, and screenwriter, best known for his pivotal role in the development of neorealism in cinema. His work is characterized by a focus on the everyday lives of ordinary people and the social issues affecting them, contrasting sharply with formalist approaches that prioritize aesthetic form over content. De Sica's films, such as 'Bicycle Thieves' and 'Umberto D.,' exemplify the realist approach, utilizing non-professional actors and on-location shooting to create an authentic portrayal of post-war Italy.