This refers to the way society expects boys and men to behave based on the meaning of being a man that has socially been accepted. This is a social, political, and historical construction; as a result, masculinity differs depending on the place and throughout time.
In a patriarchal and heteronormative system, masculinity is associated, among other things, to bravery, physical strength, heterosexuality, and qualities that are considered superior to women. These models of masculinity are harmful to the extent that they foster discrimination based on gender.