Do you Yahoo? Marissa Mayer hopes you do. The Standford graduate was the first female engineer at Google, before moving on to become the President and CEO of Yahoo. She’s led the company to meet milestones, including the acquisition of Tumblr (worth $1.1 billion). She was ranked sixth in Fortune’s 40 under 40 list in 2014, and 16th most powerful businesswoman in the world.