1930: It is considered acceptable and even friendly for an employer like Sam Spade to address an employee like Effie Perine with terms of affection such as "angel" and "precious."

Today: The use of such terms, usually associated with romance, is socially and legally forbidden, as they might be used to pressure an employee into an unwanted relationship.

1930: Steamship passage from Hong Kong to San Francisco can take weeks but is the most common way of travel.

Today: The trip from Hong Kong to San Francisco can be done by jet plane in a matter of hours.

1930: Hotels have house detectives who keep an eye on the guests to make sure that they are not bringing illegal activities into the hotel. Usually, house detectives are retired policemen.

Today: Computerized information systems make it easier for ordinary desk clerks to check background information more thoroughly than...