Untitled; Mario Merz; Mixed media on canvas; 243 x 314 cm. Photograph: Giorgio Benni, Ministry of Foreign Affairs and International Cooperation, Rome, and Google Arts & Culture

Coined by French art critic and curator Michel Tapie in 1952, the term signifies French artistic and painting styles of the 1940s and 1950s, which were produced using spontaneous brush gestures as opposed to the geometric shapes of Cubism. Also known as Informalism, it was influenced by American Abstract Expressionism and World War II.