Real gross domestic product (GDP) per capita is the ratio of real GDP to the population of the country.

It is derived from the equation:

GDP/Population = Average Income per Person (GDP per capita)

This is an interesting number to investigate as it shows the standard of living that the average person can afford in that country, thus making it much easier to compare standards of living between countries.  It should be noted that GDP does account for all of the things that affect standard of living, but GDP and standard of living seem to be related, so the higher the GDP in a country, usually the higher the standard of living.