Best Introduction to Women's History

What is the best women's history book to introduce someone to the topic of women's history? What would you recommend to someone getting started in the subject? It might be one that you used in a class or would recommend using, or it might be one that you recommend for self-education in women's history.

For this category, the book need not be recent, but it must still be in print. Nominate one to three.

_{Next category: Best New Documentary on Women's History
More nominations: 2012 Readers' Choice Awards for Women's History}