It began with a single tweet. A curious claim floated through social media: the maximum size for a PDF, supposedly, was 381 ...

Patrick Tehan/MediaNews Group/The Mercury News via Getty John Warnock, the co-founder of Adobe Systems who helped invent the PDF, has died, the tech company announced Sunday. He was 82.

John Warnock, the co-founder of Adobe, passed away on Saturday at the age of 82. "It is with profound sadness that Adobe shares the passing of the company's beloved co-founder Dr. John Warnock ...

Adobe co-founder, John Warnock, passed away at 82. Watch: How Adobe Illustrator Changed Graphic Design A video tells the story of the revolutionary software, launched in 1987, and how it changed ...