PostScript and subsequently PDF.
(Photoshop wasn't their own invention...)
That sheer technology to finally slap some graphic on a piece of paper, without jagged lines or other artefacts, without unexpected positioning, and endlessly scalable – that's just unbelievable.
And in a lesser extent, the accompanying Adobe Atlas board, which made printing in the early days of desktop publishing truly a breeze, compared to the myriad of commands necessary to take care of controlling networking protocols and handling printer communication. But that innovation has by now been replaced by many others. You even can't find any Google search result or Wikipedia article about it...
Nowadays, PostScript (and PDF) are everywhere around us. Any printed design, no matter how small or large, has come to life through Adobe's technology.
Too bad Adobe hasn't been able to achieve the same level of greatness with 3D printing. Only a few manufacturers understood the need for a decent and easy handling of the 3D printing process. But it didn't get much traction from others.
Oorspronkelijk geplaatst op Quora: What Adobe innovation has been it's greatest contribution to the artistic community?"