Remember Paul Allen: At the beginning, there was Traf-O-Data and Hendrix

"I turned to the most knowledgeable person I know," recalls Gates. "Paul explained it in a very clear and interesting way."

But Allen's nascent knowledge of computers, combined with Gates' interest and curiosity, proved to be the seed of the new society they would build.

"Even in high school, even before everyone knew what a personal computer was, he foresaw that computer chips would become super powerful and eventually give birth to a whole new industry," Gates wrote. "This idea was the cornerstone of everything we did together."

The first thing they did and could be called a business was Traf-O-Data.

At an event held in 2017 to celebrate the appointment of the Paul G. Allen School of Computer and Engineering at the University of Washington, Allen walked onto the stage violet and spoke next to a strange machine.

Before Microsoft or even Micro-Soft (its original name), it was the main company Allen-Gates. It was a computer – probably the first one built in Seattle, by a University of Waterloo student, Paul Gilbert, on the famous Intel 8008 8-bit chip – designed to automate traffic measurements.

There is no millionaire from Traf-O-Data in Seattle, but Allen felt that this failed venture was the foundation of what would happen a few years later.

"The understanding of the microprocessors that we have absorbed was critical to our future success," Allen told the UW audience, adding, "If we had not used our Traf-O-Data business … you could certainly assert that Microsoft might not have happened. I hope the lesson to be learned is that there are few real stalemates in technology and entrepreneurship. Sometimes, taking a wrong step in one direction makes you move on to another. "

Microsoft was a frugal and uncertain operation at first, and the co-founders knew it.

Greg Whitten met Paul Allen for the first time in 1978 when he visited the Compucolor offices in the Atlanta area, where he helped hack an unauthorized copy of Microsoft Basic. (It was so well done that Microsoft later forgave Compucolor for the infringement in exchange for the rights to the improvements.)

Shortly after, at the national computer conference in New York, Whitten said, Allen had invited him to the Plaza Hotel, where Microsoft had rented a suite. This is not because they were very promising: Whitten, who joined Microsoft shortly thereafter, recalls 13 employees sleeping everywhere, even upstairs. It was cheaper than any room.

Gates also enjoyed Allen's love for Hendrix, another iconic Seattleite.

"I remember playing him" Are You Experienced? For me, wrote Gates. "At that time, I had virtually no experience and Paul wanted to share this amazing music with me."

Allen also introduced Gates to another of his passions, sport.

When Mike Slade learned that Paul Allen had bought the Portland Trail Blazers in 1988, Slade sent him a long email detailing how much he loved the team he'd grown up looking at.

Slade was working at Microsoft at the time and had briefly worked with Allen before the co-founder's departure in 1983. They did not know each other well and Slade did not think that the short e-mail exchange would lead anywhere. To his surprise, a few months later, Allen invited him to a Blazers game.

Allen flew Slade on a private jet, and the two got along well. Very quickly, Slade attended every game.

"He was super generous and kind," said Slade, who in 1993 created with Allen Starwave, a software company that created ESPN.com.

Slade remembers the big whiteboard that Allen would keep in his office covered with ideas in a nutshell. He always overflowed with them, said Slade.

"If you're not careful, he'll give you more than you can handle," he laughed.

But Allen also gave Slade a lot of autonomy to run the company as he pleased, and he freely wrote checks. He was also waiting for results. Once the idea was agreed, he was ready to see it in action.

"He did not really want to know how difficult an idea was, he just wanted them to be done," said Slade.

Allen's philanthropic interests were in line with his scientific and artistic activities.

While Gates, through the huge Bill & Melinda Gates Foundation, has become synonymous with global health and development, Allen is also renowned for his work in this area.

Guy Palmer, Professor of Pathology and Infectious Diseases at Washington State University's Allen School for Global Animal Health, said that Allen had funded work in East Africa to control the number of deaths due to rabies. Thousands of children would die once a year in Africa after being bitten by rabid dogs; Allen, through the WSU, helped fund dog vaccination efforts and set up clinics to treat people if they got bitten.

He has also funded efforts to vaccinate African livestock against diseases, said Palmer. Healthier livestock helps improve farmers' incomes, and families often use this extra money for books and schooling for their daughters. "He really understood those links," said Palmer.

In 2014, Allen spent $ 100 million on efforts to combat the Ebola outbreak in West Africa. He also sought to protect African elephants by funding a census and anti-ivory trafficking programs.

Palmer, who has traveled extensively to East Africa, said that at each visit, people joined him and thanked "Mr. Paul Allen, "in a formal and reverential tone.

Closer to home, Allen has donated millions of dollars to protect ancient forests.