The shapes in the pyramid shows the relative size of classes. In South Africa the unemployed and the unskilled workers will be bigger than in developed countries. There the skilled workers and the management will be bigger.
In most countries there is some inequality between different regions - often between urban and rural areas. Rural areas tend to be involved in primary economic activities such as farming and mining. Secondary and tertiary sectors such as manufacturing and services are concentrated in the urban areas. The urban areas buy materials from rural areas, then add value and sell the goods for more. Household income in urban areas is always much higher than in rural areas. In South Africa the average household income in the mostly urban Gauteng is six times higher than the average in Limpopo which is mostly rural.
The same inequalities exist between different parts of the world. Poor countries are concentrated in the South and the East, while richer countries tend to be in the North and the West. In the next section we look at the differences between developed and developing countries.