The book entitled 4 is a story in pictures and words which, through the four elements air, water, earth and fire, goes through contemporary Italy, showing images, sometimes crude, sometimes dreamlike through photographs, and an imagery made of fiction and reality through the four stories which form the text. The book is a joint effort of the photographic collective TerraProject, which took the photographs in various corners of Italy, and Wu-Ming 2, a member of the writers' collective Wu Ming. Following the best Italian tradition of documentary photography, the book is innovative in its form, the union of photography and collective writing, and in its production. It has come to life thanks to an online crowd-funding campaign.