1930s: An immigrant like Morris Selbst, who comes into the country by jumping off a ship before it docks, can live his entire lifetime without his presence documented by the government.

Today: Government records are cross-referenced by computer. It would be virtually impossible for a man to own a business without several government agencies knowing of his existence.

1930s: The World's Fair in Chicago, dubbed the "Century of Progress," draws attendance of more than 22 million people.

Today: The ease of international travel and the knowledge of the world via the Internet make world fairs unnecessary. The last world's fair of note, Expo '98 in Lisbon, Portugal, drew 11 million people.

1930s: Gambling means placing bets with a bookmaker with underground connections.

Today: Most states have casinos, lottery, and legalized horse betting. Financing bets is more often done with a credit card than with a bookie...