Adobe PhotoShop is a type of software used to edit and manipulate scanned photographs on desktop publishing systems. Aimed at graphic designers using either a Macintosh or Windows platform, this introduction to PhotoShop begins with a description of colour theory and explains how a photograph must be analyzed before it is scanned and inserted into a desktop publishing page. It then discusses colour correction using PhotoShop, how to calibrate colour monitors to ensure accurate on-screen proofing, how to test if PhotoShop images will work with certain desktop publishing programs and much more.