Book excerpt: Our cities and neighborhoods are composed of urban building blocks and a knowledge of these elementary components is part of the basic equipment of city planning. It is absolutely essential for urban design that one understands their form and structure, their functional conditions, and the differentiation into private and public spheres, as well as the ways they are networked into their surroundings. Study of these city building blocks represents a first step toward understanding, and successfully developing the built structure of the city as a physical and social habitat. Themes are - the row, - the block, - the courtyard (the block in reverse), - the passageway, - the line, - the solitaire, - the group, - the "shed".