It's reported that Cook likes to catch seven hours of shut eye a night, meaning that he has to turn in by 8:45 p.m. to get enough rest before his early wake-up.
Source: The Huffington Post
It is known that he enjoys spending time outdoors, often hiking and riding his bicycle in his free time.
Source: TIME
When it comes to what he does outside of the office, the "intensely private" Cook prefers to keep things quiet, according to Fortune.
Source: Fortune
In addition to being at work early, Cook has previously said he's one of the last ones to leave the office, too.
Source: Inc
That doesn't stop Cook from occasionally grabbing lunch with random Apple workers in the company's cafeteria, though.
Source: Mashable
Cook also has a reputation as a demanding boss. Business Insider reported that the CEO is known for his "no-mercy" style, which includes hosting marathon meetings, questioning everything, and emailing employees "at all hours."
Source: Business Insider
When it comes to his work, Cook is reportedly collaborative and a good listener, according to TIME.
Source: TIME
It's not clear whether or not Cook enjoys a regular breakfast, but he dug into scrambled egg whites, sugar-free cereal, and unsweetened almond milk during a sit down with New York Times reporter Andrew Ross Sorkin. He also ate bacon, but prefers turkey bacon, apparently.
Source: The New York Times
The Apple CEO is mum about most of his hobbies, but it's reported that he takes fitness seriously. He's credited his Apple Watch with helping him keep in shape and even lose weight.
Source: Pakwired
Next, Cook hits the gym around 5 a.m. The CEO doesn't work out on Apple's campus, however. He prefers the privacy of an outside gym.
Source: Business Insider, Mashable
Once he's up, he gets to work reading through some of the 700 to 800 emails he gets every day. He once told ABC that he's "a bit of a workaholic" who reads "the majority of those" messages.
Source: Business Insider, Business Insider
Cook typically wakes up brutally early. According to USA Today, he usually rises at 3:45 a.m.
Source: USA Today