The problem of poverty
One of the main in the world is the problem of poverty, which is understood as the inability to provide simple and affordable for most people in this country, Living conditions. Large scale poverty, especially in developing countries, pose a serious danger not only for national but also for global sustainable development. 
The criteria of poverty
Distinguish following types of poverty:
 national;
 international.
National poverty level is the proportion of the population living below the national poverty line. In most countries of the world, including in Russia, under the national poverty line refers to income below the subsistence level, that is does not allow to cover the cost of a consumer basket — set of the required by the standards of a given country in a given period of time of goods and services. In many developed countries are considered poor people with income in size 40-50 % of the average income in the country.
The international poverty level is the income, providing the consumption of less than 2$ a day at PPS (purchasing power parity).