Sexual orientation describes an enduring pattern of attraction—emotional, romantic, sexual, or some combination of these—to the opposite sex, the same sex, or both sexes, and the genders that accompany them. These attractions are generally subsumed under heterosexuality, homosexuality, and bisexuality. Asexuality (the lack of romantic or sexual attraction to others) is sometimes identified as the fourth category. These categories are aspects of the more nuanced nature of sexual identity. For example, people may use other labels or none at all. According to the American Psychological Association, sexual orientation also refers to a person's sense of "personal and social identity based on those attractions, behaviors expressing them, and membership in a community of others who share them."

The term sexual preference largely overlaps with sexual orientation, but is distinguished in psychological research. A person who identifies as bisexual, for example, may sexually prefer one sex over the other. "Sexual preference" may also suggest a degree of voluntary choice. This is disputed in terms of sexual formation, as consensus among scholars is that sexual orientation is not a choice. There is no simple, single cause for sexual orientation that has been conclusively demonstrated, but research suggests that it is by a combination of genetic, hormonal, and environmental influences, with biological factors involving a complex interplay of genetic factors and the early uterine environment. Research over several decades has demonstrated that sexual orientation ranges along a continuum, from exclusive attraction to the opposite sex to exclusive attraction to the same sex.

Edwin Cameron (born 15 February 1953) is a South African Rhodes scholar and current Constitutional Court justice. Cameron served as a Supreme Court of Appeal judge from 2000 to 2008. He was the first senior South African official to state publicly that he was living with HIV/AIDS. Cameron was inspired to act by the stoning and stabbing to death of Gugu Dlamini after she had admitted on a Zulu language radio that she was HIV positive. He was born in Pretoria.

Cameron was educated at Pretoria Boys High School; Stellenbosch University (Anglo-American Corporation Open Scholarship, BA in Law cum laude, BA Honours in Latin cum laude, Lecturer in Latin and Classical Studies); Keble College (Rhodes Scholarship 1975-7, BA Honours First-class in Jurisprudence and Jurisprudence Prize, BCL Honours First-class and Vinerian Scholar); and the University of South Africa (LLB cum laude and medallion for the best law graduate).

He was appointed an Honorary Fellow of Keble College, Oxford in October 2003 and was a Visiting Fellow of All Souls College, Oxford 2003-4, researching 'Aspects of the AIDS Epidemic, examining in particular the denialist stance supported by SA President Mbeki'.