Brothers Thomas and John Knoll created Photoshop in 1990 for graphic designers, at a time when “electronic” photography was in its infancy and video was still analog. At George Lucas Industrial Light & Magic studio John saw the potential for digital special effects in the 1980s. As a software engineer Thomas was able to realise this and so Photoshop began. Adobe picked up Photoshop and it remains their best known software.
Still the must have software for every professional photographer, Photoshop has now become a verb used in everyday conversation.