Ujamaa was the concept that formed the basis of Julius Nyerere's social and economic development policies in Tanzania after it gained independence from Britain in 1961. The term has also come to be used as one of the seven principles of the African-American celebration of Kwanzaa.

In 1967, President Nyerere published his development blueprint, which was titled the Arusha Declaration, in which Nyerere pointed out the need for an African model of development and that formed the basis of African socialism. Ujamaa comes from the Swahili word for extended family or familyhood and is distinguished by several key characteristics, namely that a person becomes a person through the people or community.

Nyerere used Ujamaa as the basis for a national development project. He translated the Ujamaa concept into a political-economic management model through several means:

Julius Nyerere's leadership of Tanzania commanded international attention and attracted worldwide respect for his consistent emphasis upon ethical principles as the basis of practical policies. Tanzania under Nyerere made great strides in vital areas of social development: infant mortality was reduced from 138 per 1000 live births in 1965 to 110 in 1985; life expectancy at birth rose from 37 in 1960 to 52 in 1984; primary school enrolment was raised from 25% of age group (only 16% of females) in 1960 to 72% (85% of females) in 1985 (despite the rapidly increasing population); the adult literacy rate rose from 17% in 1960 to 63% by 1975 (much higher than in other African countries) and continued to rise.

The term black people is used in some socially-based systems of racial classification for humans of a dark-skinned phenotype, relative to other racial groups represented in a particular social context. Different societies apply different criteria regarding who is classified as "black", and often social variables such as class and socio-economic status also play a role, so that relatively dark-skinned people can be classified as white if they fulfill other social criteria of "whiteness" and relatively light-skinned people can be classified as black if they fulfill the social criteria for "blackness" in a particular setting.

As a biological phenotype being "black" is often associated with the very dark skin colors of some people who are classified as "black". But, particularly in the United States, the racial or ethnic classification also refers to people with all possible kinds of skin pigmentation from the darkest through to the very lightest skin colors, including albinos, if they are believed by others to have African ancestry, or to exhibit cultural traits associated with being "African-American". As a result, in the United States the term "black people" is not an indicator of skin color but of socially based racial classification.