OCCUPATION: Apple chairman and CEO
PREVIOUS APPEARANCES ON THE TIME 100: 4
PRO: The iPhone with its pronto Web access, pinpoint GPS and countless pointless-but-necessary apps might just be the niftiest gadget of Jobs' career. It's certainly one of the most popular, with some experts predicting sales of nearly 50 million this year.
CON: In January, he announced a six-month leave from Apple, a move that prompted further concerns about both his health and the company's future.