John Warnock, who helped invent the PDF and co-founded Adobe Systems, has died. He was 82.

The Silicon Valley entrepreneur and computer scientist died Saturday surrounded by family, Adobe said in a statement. The company didn’t give a cause of death or say where Warnock died.

“John’s brilliance and innovations left an indelible mark on Adobe, the technology industry and the world,” Adobe said.

Warnock worked for Xerox before he and colleague Charles Geschke created a company around a rejected idea in 1982. Nearly a decade later, Warnock outlined an early version of the Portable Document Format, or PDF, transforming the way documents are exchanged.

Originally from the Salt Lake City suburb of Holladay, Warnock described himself as an average student who later flourished in mathematics.

He earned an undergraduate in math and doctorate in electrical engineering, or computer science, from the University of Utah and maintained close ties with his home state after he retired as CEO of Adobe.

Warnock was the son of a prominent local attorney but was an average student until a teacher at Olympus High School took an interest in him, he told the University of Utah’s alumni magazine, Continuum, in 2013.

“I had an amazing teacher in high school who, essentially, completely turned me around,” Warnock said. “He was really good at getting you to love mathematics, and that’s when I got into it.”

He continued to be a self-described “mediocre” student as he earned his bachelor’s degree in mathematics and philosophy, but he made a mark while working on his master’s degree.

In 1964, he solved the Jacobson radical, an abstract algebra problem that had been a mystery since it was posed eight years before. The following year he met his wife, Marva Mullins, and married her five weeks later.

After a summer spent working at a tire shop, he decided the low-paying field of academia wasn’t for him and applied to work at IBM, starting his training in computer science. He earned a doctorate at the University of Utah, where he joined a group of cutting-edge researchers working on a Department of Defense-funded precursor to the internet in the 1960s. Even then, Warnock was working on rendering images on computers.

In the late 1970s, Warnock moved to Palo Alto, California, to work for Xerox on interactive computer graphics. There, he met Geschke and went to work developing InterPress, a printing and graphics protocol that they were convinced would be the wave of the future. When Xerox balked, they decided to create their own company.

They founded Adobe in 1982 and created PostScript, a program that helped make small-scale printing feasible for the first time. The company later created the PDF, which let people create electronic versions of documents that could be preserved and sent it to other users, who could search and review them.

With that, Adobe took off, and PDF eventually replaced many paper copies in legal, business and personal communication.

Other iconic programs, such as Adobe Illustrator and Photoshop, followed before Warnock stepped down as CEO in 2000. He and Geschke remained as co-chairs of the company’s board of directors until 2017, and Warnock remained a board member until his death.

“John has been widely acknowledged as one of the greatest inventors in our generation with significant impact on how we communicate in words, images and videos,” Adobe chair and CEO Shantanu Narayen said in an email to company employees.

After his retirement, Warnock and his wife devoted more time to hobbies such as collecting rare books, many of which he’s scanned and put online at rarebookroom.org. They also collected Native American art, including moccasins, shirts, and beadwork that has toured the country in exhibitions.

Warnock is survived by his wife and their three children.

(AP)