The idea of gender is a social construct separate from the biological category of sex. The concept emerged in the 1970s in debates spurred by the feminist movement in Europe and the United States. While there were some who believed that femininity and masculinity, and women’s and men’s roles, have their origins in unchangeable biological differences, proponents of feminism fought gender-based discrimination by arguing that it was a social phenomenon that was possible to resolve. In later discussions, gender came to be viewed not as a classification system where the categories bear equal relations to each other, but one with vertical stratification, where the man is the norm and universal, and the woman is special because of being different. Thus, rather than there being two genders – the male and the female – it was understood that there is a single gender that represents a dividing line between male and female entities. Against a backdrop of progress in the field of biology, whereas sex is a spectrum of notions including the ambiguous individual (intersex), gender is a male-female dichotomy. That is, rather than gender being defined based on sex, gender is creating the conventional idea of male/female sex. From the 1990s, under the influence of post-structuralism, differences among women received attention, rather than just those between men and women. Statements generalizing women, such as “Women are honest and incorruptible” and “Women love peace” came under fire, and the importance of recognizing differences among women, such as due to ethnicity, class, and caste, was raised. From this perspective, gender is constructed not only as the straightforward control of men over women, but through roles and actions undertaken by both men and women within their societal relations and as members of their communities.