1960s: Motown music, a simple, catchy, distinctly African-American sound, dominates the pop charts. Its performers, all African Americans, find acceptance from white audiences.

Today: Rap music, which began as a distinctly African-American sound, inspires white performers such as Eminem, a rap artist who takes the medium to new heights with his critically favored songs.

1960s: Massive inequalities between races fuel the Civil Rights movement, which is in full force.

Today: Although great strides have been made through civil rights awareness and legislation, inequalities between races still exist in America.

1960s: Many northern cities contain ghettoes, rundown slums that host specific minority groups, which typically have high crime rates. These lower-income areas help to segregate blacks from whites.

Today: Most major American cities have lower-income sections, which can host an ethnically diverse group of residents. These areas help to segregate working-class Americans from those in the...