New Delhi, Sept. 1 -- John Ternus - the engineer who built the hardware behind the iPhone, iPad and Mac - has taken over from Tim Cook as Apple's new CEO as of Tuesday, September 1. Ternus's appointment ends Cook's 15-year run, bringing to a close one of the most celebrated leadership tenures in the history of American business.

Ternus has worked on some of Apple's prominent products, including the Apple Watch, AirPods, and Apple Vision Pro.

Born on May 19, 1975, Ternus completed his Mechanical Engineering degree at the University of Pennsylvania in 1997. He joined Apple in 2001 after a four-year stint as an engineer at Virtual Research Systems.

He started on the product design team, working on screens for Apple's Mac line, before beco...