Marissa Mayer: Newest Top Female Executive

Marissa Mayer became the new CEO of Yahoo on July 17, 2012. She resigned as a vice president of Google the day before. It was a busy time for her: she had to tell her new company she and her husband were expecting a baby boy in October. An engineer who studied artificial intelligence, she had started at Google as its 20th employee in 1998. (Evan Agostini/AP Photo)