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, APA reports citing BBC.
Geschke set up Adobe in 1982, giving the world the ubiquitous 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 known as Chuck, "sparked the desktop publishing revolution".
"This is a huge loss for the entire Adobe community and the technology industry, for whom he has been a guide and hero for decades," 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.