It's not often Apple executives sit down for an interview, but to celebrate the Mac's thirtieth anniversary on Friday, Apple CEO Tim Cook talked candidly with ABC News. It's a rare look inside such a secret company. Cook, along with Apple executives Craig Federighi and Bud Tribble, discussed the culture at Apple where secrecy is their hallmark. Cook told interviewer David Muir there are locked rooms at Apple, products are under black drapes, and executives can't tell their families what type of projects are being worked on. Manufacturing Apple products in the US was also discussed, including the company's Mac Pro factory in Austin, Texas, and its new sapphire glass factory in Arizona. When pressed on whether the sapphire glass could be used for a larger iPhone or iWatch, Cook chuckled saying he couldn't answer. He jokingly added Apple is making a ring, however. The spying program in the US that's made headlines since summer 2013 was discussed.