Homosexuality and transgender are two separate concepts. Homosexuality usually refers to romantic/sexual attraction or behaviour between people of the same sex, while transgender is a matter of gender identity, meaning that a person identifies as a different gender than the one they were assigned (usually) at birth. It can also refer to an individual who identifies as neither a man nor a woman. Clear-cut distinctions between homosexuality and transgender are often impossible to make in different cultures and across time, especially where third gender social categories or gender-structured homosexuality exist.