The concept of medium in the history of contemporary art

Reflect on the concept of medium in the history of contemporary art and how it changed, in the context of Modernism and in the moment in which the idea of Modernism underwent a crisis. Choose at least two different media (for example painting, sculpture, assemblage, happening/performance, video) and briefly describe their main aesthetic features in the period of the 1940s-1960s, illustrating each medium with the work of at least one artist.