For Gates, Jobs' illness and death exemplified an important lesson about valuing what matters.
"[I]t reminds you that you've got to pick important stuff," Gates told ABC News in 2012, "because you only have a limited time."
The last time the pair spoke, "was two or three months before he passed away," Gates recalls in a 2014 interview with Rolling Stone. "And then I wrote a long letter to him after that, which he had by his bedside.
"Steve and I actually stayed in touch fairly well, and we had a couple of good, long conversations in the last year, about our wives, about life, about what technology achieved or had not achieved," says Gates.
Over the years, the pair had a famously complicated relationship as Microsoft created software and operating systems for not only Apple but its competitors, according to Walter Isaacson's book, "Steve Jobs."
In 1994, Jobs told Rolling Stone, "I think Bill Gates is a good guy. We're not best friends, but we talk maybe once a month."
Just three years later, Gates saved Apple when he agreed to make a $150 million investment in the company, which was then on the verge of bankruptcy.