The idea that an individual might have a discrete and fixed sexual orientation is a relatively recent development, one that emerged as part of the personal taxonomy projects of the 19th century. During that period, a number of different classification schemes were used to describe/conceptualizehuman sexuality. Indeed, several studies have found that much of the research regarding sexual orientation has failed to define the term at all, making it difficult to reconcile the results of different studies. However, most definitions include a psychological component (such as the direction of an individual's erotic desire) and/or a behavioural component (which focuses on the sex of theindividual's sexual partner/s). Some prefer simply to follow an individual's self-definition or identity.
More recently, queer theorists such as Eve Kosofsky Sedgwick and historians of systems of ideas such as Michel Foucault have queried the dominance of the homo(=same)/hetero(=other) binary in sexual orientation, pointing out that contemporary culture could equally well have chosen to focus onother categorisations based on different criteria, including the respective age of the partners, the sexual role played by each partner (active or passive, dominant or submissive), the power relationship between the partners or even the number of partners itself.
Sexual identity may be used as a synonym for sexual orientation, but the two are also sometimes distinguished, with identity referring toan individual's conception of themselves, and orientation referring to "fantasies, attachments and longings" and/or behavior. In addition, sexual identity (instead of "sex-identity") is sometimes used to describe a person's perception of his or her own sex, rather than sexual orientation. The term sexual preference has a similar meaning to sexual orientation, but is more commonly used outsideof scientific circles by people who believe that sexual orientation is, in whole or part, a matter of choice.
Heterosexuality is sexual or romantic attraction between opposite sexes, and is the most common sexual orientation among humans. The current use of the term has its roots in the broader 19th century tradition of personality taxonomy. These continue to influence the development of themodern concept of sexual orientation, gaining associations with romantic love and identity in addition to its original, exclusively sexual meaning.
The adjective heterosexual is used for intimate relationships and/or sexual relations between male and female individuals, who may or may not identify themselves as straight. Heterosexuality, as an identifier, is usually contrasted with homosexualityand bisexuality. The term straight is used predominantly to refer to self-identified heterosexuals of either sex. Unlike lesbian, there is no gender-specific term that is only used for self-identified heterosexual females.
Bisexuality is a sexual orientation which refers to the aesthetic, romantic, and/or sexual attraction of individuals to other individuals of either their own or the oppositegender or sex. Most bisexuals are not equally attracted to men and women, and may even shift between states of finding either sex exclusively attractive over the course of time. However, some bisexuals are and remain fairly static in their level of attraction throughout their adult life.
In the mid-1950s, Alfred Kinsey devised the Kinsey scale in an attempt to measure sexual orientation....