When discussing sex rather than gender, the terms male and female are appropriate. However, in humans, separating sex from gender is nearly impossible, as gender roles and expectations socialize people to behave in ways that align with what is considered masculine or feminine. Furthermore, transgender and gender nonconforming (TGNC) people may have a gender identity that does not match the sex they were assigned at birth. This entry concentrates primarily on cisgender people (or people who identify with their assigned birth sex) and will refer to those of different sexes as women and men.