Warnock and Charles Geschke formed Adobe Systems in 1982. Ten years later they launched Acrobat Reader and its associated Portable Document Format (PDF), which have become worldwide standards, along with Adobe's Postscript page description language. To date, more than 600 million copies of Acrobat Reader have been downloaded free of charge.
"Acrobat is now Adobe's biggest product, yet it started very slowly," Warnock said. "This was before the internet explosion, and most people just did not get the value of a portable document - why would you want to send a document from A to B electronically? Our board of directors tried to kill it."
The partners had worked together at the Xerox Palo Alto Research Centre, where Warnock's job was to introduce device-independent graphics at a time when all graphics were about bit-map manipulation - for example, a separate set of bitmaps was needed for each type size.
Warnock and Geschke left to form Adobe Systems and their pedigree soon brought them a visit from Steve Jobs, founder of Apple Computers. "We showed him the early version of Postscript and he gave us an £800,000 advance against royalties to build Laserwriter," Warnock said.
This contract led almost by accident to the development of the PDF. Jobs wanted to demonstrate the Laserwriter at its launch and Warnock used Postscript to produce a standard US tax form.
He created lots of subroutines, for example, to print boxes, but it took 2.5 minutes to print. So he used special Postscript features to create a much simpler page file, which printed far more quickly.
When the Laserwriter was launched in 1985 it brought Adobe instant recognition.
"On a low-cost machine we had combined images, text and graphics," Warnock said. "And we had done it in a device-independent way, so you could go to a high- or low-resolution device. The publishing world saw that this was a huge economic breakthrough. IBM selected Postscript for its laser printers and Hewlett-Packard soon followed."
In 1991 the growth of networks and the emergence of the internet set Warnock thinking about the Postscript programming tricks he had used to speed up the Laserwriter demonstration. Acrobat and PDF were launched in 1993.
"Today every magazine, flyer, TV commercial, movie, billboard and sign probably has a little bit of Adobe technology in it," he said. "We feel very fortunate to have had such a profound effect on printing and publishing."