Heterosexuality is not normal, it's just common.

—Dorothy Parker[1]

Heterosexuality (or straightness) is the orientation of individuals who identify as one binary gender (e.g., woman or man) and are attracted to the other binary gender.

Orientation, like gender, is a self-concept. This means that looking at somebody's relationships cannot be used as the defining factor of their orientation. For example, a cis woman who is attracted to a trans man might identify as straight/heterosexual, or she might identify as pansexual, bisexual, androphilic, or something else.

See also