Bisexuality

Bisexuality is romantic attraction, sexual attraction, or sexual behavior toward both males and females. It may also be defined as the attraction to more than one gender, to people of both the same and different gender, or the attraction to people regardless of their sex or gender identity (pansexuality).

The term bisexuality is mainly used for people who experience both heterosexual and homosexual attraction. Bisexuality is one of the three main classifications of sexual orientation along with heterosexuality and homosexuality, all of which exist on the heterosexual–homosexual continuum. A bisexual identity does not necessarily equate to equal sexual attraction to both sexes; commonly, people who have a distinct but not exclusive sexual preference for one sex over the other also identify themselves as bisexual.

Scientists do not know the exact determinants of sexual orientation, but they theorize that it is caused by a complex interplay of genetic, hormonal, and environmental influences, and do not view it as a choice. Although no single theory on the cause of sexual orientation has yet gained widespread support, scientists favor biologically based theories. There is considerably more evidence supporting nonsocial, biological causes of sexual orientation than social ones, especially for males.

Bisexuality has been observed in various human societies, as well as elsewhere in the animal kingdom, throughout recorded history. The term bisexuality, like the terms hetero- and homosexuality, was coined in the 19th century by Charles Gilbert Chaddock.