You use herself to refer to a woman, girl, or female animal.

In written English, herself is sometimes used to refer to a person without saying whether that person is a man or a woman. Some people dislike this use and prefer to use 'himself or herself' or 'themselves'.

Herself is sometimes used to refer to a country or nation.

People sometimes use herself to refer to a car, machine, or ship.

You use herself to emphasize the person or thing that you are referring to. Herself is sometimes used instead of 'her' as the object of a verb or preposition.