Short answers, pulled from the story.
White flight describes a sudden or gradual large-scale migration of white people from areas becoming more racially or ethnoculturally diverse to more racially homogenous suburban or exurban regions. This movement has also been applied to other migrations by whites from older, inner suburbs to rural areas, as well as from the American Northeast and Midwest to the milder climate in the South and West.
The terms became popular starting in the 1950s and 1960s, especially in the United States. Migration of middle-class white populations was observed during the civil rights movement in the 1950s and 1960s out of cities such as Baltimore, Cleveland, Detroit, Kansas City and Oakland.
Political scientist Morton Grodzins identified that once the proportion of non-whites exceeds the limits of the neighborhood's tolerance for interracial living, whites move out. Grodzins termed this phenomenon the tipping point in the study of white flight.
About 800,000 out of an earlier total population of 5.2 million whites left post-apartheid South Africa after 1995, according to a 2009 report in Newsweek. The country has suffered a high rate of violent crime, a primary stated reason for emigration.
A study of school choice in Copenhagen found that if the percentage of immigrant children rose above 35%, Danes are far more likely to choose other schools. If the percentage of immigrant children rises above this level, parental choice of schools is significantly affected.