1970: Movies are primarily watched in large movie theaters, which change their offerings frequently. Still, there is relatively little choice on any given day.

Today: With video cassettes and DVDs, a movie watcher has literally thousands of choices available for little cost. Movie theaters still show big-budget movies, but studios make most of their money from the sale and rental of videos and DVDs.

1970: Most movie theaters are independently owned and operated, choosing what to show and when to show it. Managers are relatively free to show the latest big attractions from Hollywood or low-budget reruns.

Today: Most movie theaters across the country show the same movies at the same time. Small-budget and independent movies and theaters showing movies that are not new are rare.

1970: No African American has won the Pulitzer Prize for Fiction or the Nobel Prize in literature.

Today: Excellent literature by...