One recent estimate claims there are 4.732 billion buildings on Earth, but it’s difficult to establish a credible methodology to count them. Is Manhattan’s Rockefeller Center, created out of swaggering pride and ambition, in the same category as a shanty hut in an Algerian bidonville? Unless you live in a desert, buildings are unavoidable, making architecture not just a necessity for survival but the art form most pregnant with meaning.