No. 4: IBM, Tal Rabin

Name: Tal Rabin

Job title: Manager and a research staff member of the cryptography research group at IBM’s T.J. Watson Research Center.

Why she's powerful: Rabin's early career was almost like the movie "Good Will Hunting." When she was a student, she solved a math problem that experts thought couldn't be solved. (It's complicated, something to do with calculating numbers when most of them are not known, she told Business Insider).

At IBM she leads a team working on inventing whole new ways to secure computer data. The work is so advanced that Rabin was awarded the top honor at The Anita Borg Institute's 2014 Women of Vision awards.

She's also chairs conferences and professional organizations in her field. She has a doctorate in computer science from the Hebrew University of Jerusalem and was a postdoctoral Fellow at the MIT Laboratory for Computer Science.