Black people is a term usually referring to a racial group of humans with a dark skin color, but the term has also been used to categorise a number of diverse populations into one common group. Some definitions of the term include only people of relatively recent Sub Saharan African descent (see African diaspora), while others extend the term to any of the populations characterized by dark skin color, a definition that also includes certain populations in Oceania, Southeast Asia,   southern South Asia, and the southern Middle East .
The evolution of dark skin is intrinsically linked to the loss of body hair in humans.By 1.2 million years ago, all people having descendants today had the same receptor protein of today's Africans; their skin was dark, and the intense sun killed off the progeny with any lighter skin that resulted from mutational variation in the receptor protein. This is significantly earlier than the speciation of Homo sapiens from Homo erectus some 250,000 years ago.
Dark skin helps protect against skin cancer that develops as a result of ultraviolet light radiation, causing mutations in the skin. Furthermore, dark skin prevents an essential B vitamin, folate, from being destroyed. Therefore, in the absence of modern medicine and diet, a person with dark skin in the tropics would live longer, be healthier and likelier to reproduce than a person with light skin. White Australians have some of the highest rates of skin cancer as evidence of this expectation. Conversely, as dark skin prevents sunlight from penetrating the skin it hinders the production of vitamin D3. Hence when humans migrated to less sun-intensive regions in the north, low vitamin D3 levels became a problem and lighter skin colors started appearing. The people of Europe, who have low levels of melanin, naturally have an almost colorless skin pigmentation, especially when untanned. This low level of pigmentation allows the blood vessels to become visible and gives the characteristic pale pink color of white people. The primary difference in skin color between blacks and whites is however a minor genetic difference accounting for just one letter in 3.1 billion letters of DNA.
See also: Demographics of Africa. Sub-Saharan Africa is a common if imprecise term that encompasses African countries located south of the Saharan Desert. It is commonly used to differentiate the region culturally, ecologically, politically and, more controversially, racially, from other parts of the continent. Because the indigenous people of this region are primarily dark-skinned, it is sometimes used as a euphemism for "Black Africa". Some criticize the use of the term, because, having become in many quarters synonymous with Black Africa, it can leave the mistaken impression that there are not indigenous Black populations in North Africa. Furthermore, the Sahara cuts across countries such as Mauritania, Mali, Niger, Chad, and Sudan, leaving some parts of them in North Africa and some in sub-Saharan Africa.
Owen 'Alik Shahadah argues that the term sub-Saharan Africa has racist overtones:
However, some black Africans prefer to be culturally distinguished from those who live in the north of the continent.
In South Africa during the apartheid era, the population was classified into four groups: Black, White, Asian (mostly Indian), and Coloured. The Coloured group included people of mixed Bantu, Khoisan, and European descent (with some Malay ancestry, especially in the Western Cape). The Coloured definition occupied an intermediary position between the Black and White definitions in South Africa.
The apartheid bureaucracy devised complex (and often arbitrary) criteria in the Population Registration Act to determine who belonged in which group. Minor officials administered tests to enforce the classifications. When it was unclear from a person's physical appearance whether a person was to be considered Colored or Black, the "pencil test" was employed. This involved inserting a pencil in a person's hair to determine if the hair was kinky enough for the pencil to get stuck.
During the apartheid era, the Coloureds were oppressed and discriminated against. However, they did have limited rights and overall had slightly better socioeconomic conditions than Blacks. In the post-apartheid era the government's policies of affirmative action have favored Blacks over Coloureds. Some South Africans categorized as Black openly state that Coloureds did not suffer as much as they did during apartheid. The popular saying by Coloured South Africans to illustrate this dilemma is:
Other than by appearance, Coloureds can be distinguished from Blacks by language. Most speak Afrikaans or English as a first language, as opposed to Bantu languages such as Zulu or Xhosa. They also tend to have more European-sounding names than Bantu names.
See also: Afro-Arab. Black African and Near Eastern peoples have interacted since prehistoric times.  Some historians estimate that as many as 14 million black slaves crossed the Red Sea, Indian Ocean, and Sahara Desert in the Arab slave trade from 650 to 1900 CE. 
The Afro-Asiatic languages, which include Semitic languages such as Arabic and Hebrew, are believed by some scholars to have originated in Ethiopia. This is because the region has very diverse language groups in close geographic proximity, often considered a telltale sign for a linguistic geographic origin.
In more recent times, about 1000 CE, interactions between blacks and Arabs resulted in the incorporation of extensive Arabic vocabulary into Swahili, which became a useful lingua franca for merchants. Some of this because of the slave trade; the history of Islam and slavery shows that the major juristic schools traditionally accepted the institution of slavery. As a result, Arab influence spread along the east coast of Africa and to some extent into the interior (see East Africa). Timbuktu was a trading outpost that linked west Africa with Berber, Arab, and Jewish traders throughout the Arab World. As a result of these interactions many Arab people in the Middle East have black ancestry and many blacks on the east coast of Africa and along the Sahara have Arab ancestry.
According to Dr. Carlos Moore, resident scholar at Brazil's Universidade do Estado da Bahia, Afro-multiracials in the Arab world self-identify in ways that resemble Latin America. He claims that black-looking Arabs, much like black-looking Latin Americans, consider themselves white because they have some distant white ancestry.
Moore also claims that a film about Egyptian President Anwar Sadat had to be canceled when Sadat discovered that an African-American had been cast to play him. In fact, the 1983 television movie Sadat, starring Louis Gossett, Jr., was not canceled. The Egyptian government refused to let the drama air in Egypt, partially on the grounds of the casting of Gossett. The objections, however, did not come from Sadat, who had been assassinated two years earlier.
Sadat's mother was a black Sudanese woman and his father was a lighter-skinned Egyptian. In response to an advertisement for an acting position he remarked, "I am not white but I am not exactly black either. My blackness is tending to reddish".
Fathia Nkrumah was another Egyptian intimately tied with black Africa. She was the late wife of Ghanaian revolutionary Kwame Nkrumah, whose marriage was seen as helping plant the seeds of cooperation between Egypt and other African countries as they struggled for independence from European colonization, which in turn helped advance the formation of the African Union.
In general, Arabs had a more positive view of black women than black men, even if the women were of slave origin. More black women were enslaved than men, and, because the Qur'an was interpreted to permit sexual relations between a male master and his female slave outside of marriage,  many mixed race children resulted. When an enslaved woman became pregnant with her Arab captor's child, she became “umm walad” or “mother of a child”, a status that granted her privileged rights. The child would have prospered from the wealth of the father and been given rights of inheritance. Because of patrilineality, the children were born free and sometimes even became successors to their ruling fathers, as was the case with Sultan Ahmad al-Mansur, (whose mother was a Fulani concubine), who ruled Morocco from 1578-1608. Such tolerance, however, was not extended to wholly black persons, even when technically "free," and the notion that to be black meant to be a slave became a common belief. The term "abd," (Arabic: عبد,) "slave," remains a common term for black people in the Middle East, often though not always derogatory.
See also: Afro-Turks. Beginning several centuries ago, a number of sub-Saharan Africans were brought by slave traders during the Ottoman Empire to plantations between Antalya and Istanbul in modern-day Turkey. Some of their descendants remain, mixed with the rest of the population in these areas, and many migrated to larger cities. Some came from the island of Crete following the population exchange between Greece and Turkey in 1923.
During the Ottoman rule, black African slaves (usually transferred over Egypt) were brought to Cyprus and sold to Muslim families. Many of their descendants rose to prominent positions and assimilated into the Turkish Cypriot community, creating a sizeable multiracial population today.
Ulcinj in Montenegro had its own black community - descendent of the Ottoman slave trade that had flourished here. The Ottoman Army counted thousands of black African soldiers in its ranks. The army sent to Balkans during the Austro-Turkish War of 1716–18 included 24,000 men from Africa.
Approximately 12 million Africans were shipped to the Americas during the Atlantic slave trade from 1492 to 1888. Today their descendants number approximately 150 million, most of whom live in the United States, the Caribbean and Latin America, including Brazil. Many have a multiracial background of African, Amerindian, European and Asian ancestry. The various regions developed complex social conventions with which their multi-ethnic populations were classified.
See main article: African American.
See also: African immigration to the United States.
In the first 200 years that blacks had been in the United States, they commonly referred to themselves as Africans. In Africa, people primarily identified themselves by tribe or ethnic group (closely allied to language) and not by skin color. Individuals would be Asante, Igbo, Bakongo or Wolof. But when Africans were brought to the Americas they were forced to give up their ethnic affiliations for fear of uprisings. The result was the Africans had to intermingle with other Africans from different ethnic groups. This is significant as Africans came from a vast geographic region, the West African coastline stretching from Senegal to Angola and in some cases from the south east coast such as Mozambique. A new identity and culture was born that incorporated elements of the various tribal groups and of European cultural heritage, resulting in fusions such as the Black church and Black English. This new identity was now based on skin color and African ancestry rather than any one tribal group.
In March 1807, Britain, which largely controlled the Atlantic, declared the trans-atlantic slave trade illegal, as did the United States. (The latter prohibition took effect January 1, 1808, the earliest date on which Congress had the power to do so under Article I, Section 9 of the United States Constitution.)
By that time, the majority of blacks were U.S.-born, so use of the term "African" became problematic. Though initially a source of pride, many blacks feared its continued use would be a hindrance to their fight for full citizenship in the US. They also felt that it would give ammunition to those who were advocating repatriating blacks back to Africa. In 1835 black leaders called upon black Americans to remove the title of "African" from their institutions and replace it with "Negro" or "Colored American". A few institutions however elected to keep their historical names such as African Methodist Episcopal Church. "Negro" and "colored" remained the popular terms until the late 1960s.
The term black was used throughout but not frequently as it carried a certain stigma.In his 1963 "I Have a Dream" speech, Martin Luther King, Jr. uses the terms Negro 15 times and black 4 times. Each time he uses black it is in parallel construction with white (e.g., black men and white men). With the successes of the civil rights movement a new term was needed to break from the past and help shed the reminders of legalized discrimination. In place of Negro, black was promoted as standing for racial pride, militancy and power. Some of the turning points included the use of the term "Black Power" by Kwame Toure (Stokely Carmichael) and the release of James Brown's song "Say It Loud - I'm Black and I'm Proud".
In 1988 Jesse Jackson urged Americans to use the term African American because the term has a historical cultural base. Since then African American and black have essentially a coequal status. There is still much controversy over which term is more appropriate. Some strongly reject the term African American in preference for black citing that they have little connection with Africa. Others believe the term black is inaccurate because African Americans have a variety of skin tones. Surveys show that when interacting with each other African Americans prefer the term black, as it is associated with intimacy and familiarity. The term "African American" is preferred for public and formal use. The appropriateness of the term "African American" is further confused, however, by increases in black immigrants from Africa, the Caribbean and Latin America. The more recent black immigrants may sometimes view themselves, and be viewed, as culturally distinct from native descendants of African slaves.
The U.S. census race definitions says a black is a person having origins in any of the black racial groups of Africa. It includes people who indicate their race as "Black, African Am., or Negro," or who provide written entries such as African American, Afro American, Kenyan, Nigerian, or Haitian. However, the Census Bureau notes that these classifications are socio-political constructs and should not be interpreted as scientific or anthropological.
A considerable portion of the U.S. population identified as black actually have some Native American or European American ancestry. For instance, genetic studies of African American people show an ancestry that is on average 17-18% European.
Historically, the United States used a colloquial term, the one-drop rule, to designate a black person as any person with any known African ancestry. Outside of the US, some other countries have adopted the practice, but the definition of who is black and the extent to which the one drop "rule" applies varies from country to country.
The one drop rule may have originated as a means of increasing the number of black slaves and been maintained as an attempt to keep the white race pure. . One of the results of the one drop rule was uniting the African American community and preserving an African identity. Some of the most prominent civil rights activists were multiracial, and advocated equality for all.
President Barack Obama self-identifies as black and African American interchangeably. According to a Williams Identity Survey conducted by Zogby International interactive poll conducted November 1-2, 2006, among those who voted, 55 percent of whites voters and 61 percent of Hispanics voters classified him as biracial instead of black after being told that his mother is white, and 66% of Black voters classified Obama as black. Another poll conducted by the same group returned results that forty-two percent of African-Americans voters described Tiger Woods as black, as did 7% of white voters.
The concept of blackness in the United States has been described as the degree to which one associates themselves with mainstream African American culture and values. This concept is not so much about skin color or tone but more about culture and behavior. Blackness can be contrasted with "acting white" where black Americans are said to behave with assumed characteristics of stereotypical white Americans, with regard to fashion, dialect and taste in music.
The notion of blackness can also be extended to non-black people. Toni Morrison once described Bill Clinton as the first black president, because of his warm relations with African Americans, his poor upbringing and also because he is a jazz musician. Christopher Hitchens was offended by the notion of Clinton as the first black president noting "we can still define blackness by the following symptoms: alcoholic mothers, under-the-bridge habits...the tendency to sexual predation and shameless perjury about the same" Some black activists were also offended, claiming Clinton used his knowledge of black culture to exploit black people like no other president before for political gain, while not serving black interests. They note his lack of action during the Rwanda genocide and his welfare reform which led to the worst child poverty since the 1960s along with the fact that the number of blacks in jail increased during his administration.
The question of blackness also arose in Democrat Barack Obama's 2008 presidential campaign. Commentators such as Time magazine have questioned whether Obama, who was elected the first black President of the United States, is black enough, as his mother is white American, and his father is a black Kenyan immigrant. Obama refers to himself interchangeably as black and African American.
See main article: Race in Brazil. The topic of race in Brazil is a complex and diverse one. A Brazilian child was never automatically identified with the racial type of one or both parents, nor were there only two categories to choose from. Between a pure black and a very light mulatto over a dozen racial categories would be recognized in conformity with the combinations of hair color, hair texture, eye color, and skin color. These types grade into each other like the colors of the spectrum, and no one category stands significantly isolated from the rest. That is, race referred to appearance, not heredity.
There is some disagreement among scholars over the effects of social status on racial classifications in Brazil. It is generally believed that upward mobility and education results in reclassification of individuals into lighter skinned categories. The popular claim is that in Brazil poor whites are considered black and wealthy blacks are considered white. Some scholars disagree arguing that whitening of one's social status may be open to people of mixed race, but a typically black person will consistently be identified as black regardless of wealth or social status. 
A philosophy of whitening emerged in Brazil in the 19th century. Until recently the government did not keep data on race. However, statisticians estimate that in 1835 half the population was black, one fifth was Pardo (brown) and one fourth white. By 2000 the black population had fallen to only 6.2% and the Pardo had increased to 40% and white to 55%. Essentially most of the black population was absorbed into the multiracial category by intermarriage. A recent study found that at least 29% of the middle class white Brazilian population had some recent African ancestry.
Because of the ideology of miscegenation, Brazil has avoided the polarization of Society into black and white. The bitter and sometimes violent racial tensions that divide the US are notably absent in Brazil.However the philosophy of the racial democracy in Brazil has drawn criticism from some quarters. Brazil has one of the largest gaps in income distribution in the world. The richest 10% of the population earn 28 times the average income of the bottom 40%. The richest 10 percent is almost exclusively white. One-third of the population lives under the poverty line of which blacks and other non-whites account for 70 percent of the poor.
In the US blacks earn 75% of what whites earn, in Brazil non-whites earn less than 50% of what whites earn. Some have posited that Brazil does in fact practice the one drop rule when social economic factors are considered. This because the gap income between blacks and other non-whites is relatively small compared with the large gap between whites and non-whites. Other factors such as illiteracy and education level show the same patterns. Unlike in the US where African Americans were united in the civil rights struggle, in Brazil the philosophy of whitening has helped divide blacks from other non-whites and prevented a more active civil rights movement.
Though Afro-Brazilians make up half the population there are very few black politicians. The city of Salvador, Bahia for instance is 80% Afro-Brazilian but has never had a black mayor. Critics indicate that in US cities like Detroit and New Orleans that have a black majority, have never had white mayors since first electing black mayors in the 1970s.
Non-white people also have limited media visibility. The Latin American media, in particular the Brazilian media, has been accused of hiding its black and indigenous population. For example the telenovelas or soaps are said to be a hotbed of white, largely blonde and blue/green-eyed actors who resemble Scandinavians or other northern Europeans more than they resemble the typical whites of Brazil, who are mostly of Southern European descent.  
These patterns of discrimination against non-whites have led some to advocate for the use of the Portuguese term 'negro' to encompass non-whites so as to renew a black consciousness and identity, in effect an African descent rule.
There are several groups of dark-skinned people who live in various parts of Asia, Australia and Oceania. They include the Indigenous Australians, the Melanesians (now divided into Austronesian-speaking populations and Papuans, and including the great genetic diversity of New Guinea), the Andamanese people of the Andaman and Nicobar Islands of the Indian Ocean, the Semang people of the Malay peninsula, the Aeta people of Luzon, the Ati of Panay, the Vedda people of Sri Lanka, and various indigenous peoples sometimes collectively known as Negritos.
By their external physical appearance (phenotype) such people resemble Black Africans with dark skin and sometimes tightly coiled hair. There have been suggestions of a Black African origin. However, in the case of the Andamanese people, a study conducted by the NCBI indicated that the Andamanese people posessed closer affinities with the Southeast Asian population than with the Black African population. 
See main article: Afro-European.
For many centuries throughout the Age of Discovery and the colonial empires, black people came from the colonies to the "mother country", either voluntarily (sometimes for education) or under duress (sometimes as slaves). Even prior to that, the Arab slave trade brought large numbers of Africans to the furthest reaches of Europe; for example, Peter the Great took as a protégé Abram Petrovich Gannibal, whose descendants number poet Alexandr Pushkin and Hugh Grosvenor, heir apparent to Britain's wealthiest aristocrat. Most of the black people living in Europe, however, have their origins in relatively recent waves of immigration. Since the decolonisation of the mid-twentieth century, substantial black populations have moved to certain countries in Europe; other European countries have very few black people. At present, black people have limited visibility in mainstream European society, except in a handful of roles such as sporting activities.
According to National Statistics, as of the 2001 census, there are over a million black people in the United Kingdom; 1% of the total population describe themselves as "Black Caribbean", 0.8% as "Black African", and 0.2% as "Black other". The largest single number comes from Nigeria, just over 88,000 . Britain encouraged workers from the Caribbean after World War II; the first symbolic movement was those who came on the ship the Empire Windrush. The preferred official umbrella term is "black and minority ethnic" (BME), but sometimes the term "black" is used on its own, to express unified opposition to racism, as in the Southall Black Sisters, which started with a mainly British Asian constituency. Black Britons tend to live in the cities, whereas the white population is moving more to suburbs and the countryside (see white flight). The total Black British population is currently thought to be much higher with around 2 million Nigerians in the country alone.
As African states became independent in the 1960s, the Soviet Union offered them the chance to study in Russia; over 40 years, 400,000 African students came, and many settled there.  This extended beyond the Soviet Union to many countries of the Eastern bloc.
A cultural classification of people as "black" exists in Russia. Certain groups of people who are ethnically different, and generally darker, than ethnic Russians are pejoratively referred to as "blacks" (chernye), and face specific sorts of social exclusion (see Racism in Russia). Roma, Georgians, and Tatars fall into this category. Those referred to as "black" are from the former Soviet republics, predominantly peoples of the Caucasus, e.g. Chechens. Although "Caucasian" is used in American English to mean "white people", in Russian - and most other varieties of English - it only refers to the Caucasus, not European people in general.
See also: Negroid and mulatto people of Russia in russian Wikipedia.
See main article: Afrocentrism and Ancient Egyptian race controversy. A controversy over the skin color and ethnic origins of the ancient Egyptians was sparked as part of the Afrocentric debate. Afrocentrist scholars such as Cheikh Anta Diop contend that ancient Egypt was primarily a "black civilization". One source cited in support of their argument is Herodotus, who wrote around 450 B.C. that "Colchians, Ethiopians and Egyptians have thick lips, broad nose, woolly hair and they are burnt of skin." However, Classical scholar Frank Snowden, Jr. cautions against the reliance on accounts by ancient writers to describe the physical characteristics of other ancient peoples, as they held different connotations from those of modern-day terminology in the West. He also points out that other ancient writers clearly distinguished between Egyptians and Ethiopians.
Keita and Boyce confront this issue in a 1996 article entitled, "The Geographical Origins and Population Relationships of Early Ancient Egyptians". As anthropologists, they point out the danger in relying on ancient interpretation to reveal for us the biological make up of a population. In any case they contend, the relevant data indicates greater similarity between Egyptians and Ethiopians than the former group with the Ancient Greeks.
Ancient Egyptians are often portrayed in modern media as Caucasians, and many people, Afrocentrists in particular, have been critical of this. According to Egyptologists, ancient Egypt was a multicultural society of Middle Eastern, Northeast African, and Saharan influences.  Anthropological and archaeological evidence shows that an Africoid element was evident in ancient Egypt, which was predominant in Abydos in the First dynasty of Egypt. 
According to some historians, the tale in Genesis 9 in which Noah cursed the descendants of his son Ham with servitude was a seminal moment in defining black people, as the story was passed on through generations of Jewish, Christian and Islamic scholars. According to columnist Felicia R. Lee, "Ham came to be widely portrayed as black; blackness, servitude and the idea of racial hierarchy became inextricably linked." Some people believe that the tradition of dividing humankind into three major races is partly rooted in tales of Noah's three sons repopulating the Earth after the Deluge and giving rise to three separate races.
The biblical passage, Book of Genesis 9:20-27, which deals with the sons of Noah, however, makes no reference to race. The reputed curse of Ham is not on Ham, but on Canaan, one of Ham's sons. This is not a racial but geographic referent. The Canaanites, typically associated with the region of the Levant (Palestine, Lebanon, etc) were later subjugated by the Hebrews when they left bondage in Egypt according to the Biblical narrative.  The alleged inferiority of Hamitic descendants also is not supported by the Biblical narrative, nor claims of three races in relation to Noah's sons. Shem for example seems a linguistic not racial referent. In short the Bible does not define blacks, nor assign them to racial hierarchies.
Historians believe that by the 19th century, the belief that blacks were descended from Ham was used by southern United States whites to justify slavery. According to Benjamin Braude, a professor of history at Boston College:
Author David M. Goldenberg contends that the Bible is not a racist document. According to Goldenberg, such racist interpretations came from post-biblical writers of antiquity like Philo and Origen of Alexandria, who equated blackness with darkness of the soul.