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In recent decades these countries have been experiencing a transition of population from rural areas to urban areas. In such a transition people move to the city either as individuals or a nuclear family. The individual separates from the familiar tribal frame in the rural areas or in the desert. While in the city, he or she joins thousands of individuals like him or her, who also live urban life, leaving behind them their traditional and tribal way of life. Some people join professional organizations or unions that protect their interests and promote them. Others join ideological or political organizations (such as socialist, democratic or religious). The characteristic feature of these organizations is that they are not based on family ties, which cannot be replaced, but on interests and ideology which certainly can be.