Heterosexuality is a sexual orientation. Heterosexual people are sexually attracted to the opposite gender, and this may involve romantic feelings, or sexual activity. Another less formal word for heterosexual is straight.[1]
People who are not heterosexual may be homosexual, bisexual or asexual. Many people in Western society are heteronormative, which means that they believe that heterosexuality is better than other forms of sexuality. This often leads to discrimination.[1]
Sexual orientation is thought to be caused by genetics and hormones when a baby is growing in its mother. Hormones play a role in making men and women have differences in a region of the brain called the sexually dimorphic nucleus, which is involved in sexual attraction. Men have larger clusters in the hypothalamus than women, similar to other mammals.[1]
In the Catholic Church and many Christian churches as well as in Islam and Judaism, a marriage can only be made in a heterosexual pair - man and woman. Marriage that is done in homosexual pair is often seen as a serious sin by those religions.
