Despite the current growing popularity of the computer science (CS) major, women remain sorely underrepresented in the field, continuing to earn only 18% of bachelor's degrees. Understanding women's low rates of participation in CS is important given that the demand for individuals with CS training has grown sharply in recent years. Attracting and retaining more women to high-paying fields like CS may also help narrow the gender pay gap. Further, it is important that women participate in developing new technology so that technology advances serve the needs of both women and men. This paper explores the background characteristics, career aspirations, and self-perceptions of 1,636 female first-year college students in the United States who intend to major in CS and compares them with 4,402 male CS aspirants as well as with 26,642 women planning to major in other STEM sub-fields. The findings reveal a unique profile of women who pursue the CS major and notes many significant differences between men and women in CS and between women in CS and those in other STEM fields. For instance, women in CS tend to earn lower high school grades than women in other STEM fields, but earn higher SAT verbal scores. They also rate themselves higher than men in CS and women in other STEM fields on measures of their artistic ability, but rate themselves lower on other self-ratings, including academic and leadership ability. Further, women in CS are more likely to be undecided in their career plans than men in CS and women in other STEM fields. Understanding the unique characteristics of women in CS will help inform policies and recruitment programs designed to address the gender gap in computing.