Charles Geschke, the co-founder of the software company Adobe who helped develop the Portable Document Format or PDF, has died at the age of 81.
Geschke acknowledged Adobe in 1982, giving the earth the ever-present PDF software, among many other audio-visual innovations.
He made headlines 10 years later when he was kidnapped at gunpoint and held for ransom before being released unhurt after a four-day ordeal.
Geschke died in California on Friday.
Adobe CEO Shantanu Narayen said Geschke, widely referred to as Chuck, “sparked the publication revolution”.
“This could also be an enormous loss for the entire Adobe community and thus the technology industry, for whom he has been a guide and hero for several years,” he wrote in an email to the company’s employees.
“As co-founders of Adobe, Chuck and John Warnock developed ground-breaking software that has revolutionized how people create and communicate,” he said.
Geschke and Warnock were liable for transformative software inventions, including PDF, Acrobat, Illustrator, Premiere Pro, and Photoshop, Mr. Narayen said.
In 1992, Geschke was kidnapped on an occasion that made national headlines.
He was held at gunpoint in his office and delivered to Hollister, California, for four days.
Geschke was freed after a suspect, found with $650,000 (£470,000) in ransom, took police to the situation where he was being held, Associated Press reported.
In 2009, President Barack Obama awarded Geschke and Warnock the National Medal of Technology.
“He was a humble, humble man – I can say that, as his wife,” Nan Geschke told Mercury News. “He was very pleased with his success, of course, but he was very circumspect about what proportion he had to try too thereupon.”