Adobe Photoshop

Adobe Photoshop, or simply Photoshop, is a graphics editing program developed and published by Adobe Systems. It is the current market leader for commercial bitmap and image manipulation software, and is the flagship product of Adobe Systems. It has been described as "an industry standard for graphics professionals" and was one of the early "killer applications" on the PC.

Adobe's 2005 "Creative Suite" rebranding led to Adobe Photoshop 8's renaming to Adobe Photoshop CS. Thus, Adobe Photoshop CS4 is the 11th major release of Adobe Photoshop. The CS rebranding also resulted in Adobe offering numerous software packages containing multiple Adobe programs for a reduced price. Adobe Photoshop is included in most of Adobe's Creative Suite offerings.

Photoshop's popularity, combined with its high retail price, makes Photoshop's piracy rate relatively high. Adobe countered by including SafeCast DRM starting with Adobe Photoshop CS.

In 1987, Thomas Knoll, a PhD student at the University of Michigan, began writing a program on his Macintosh Plus to display grayscale images on a monochrome display. This program, called Display, caught the attention of his brother John Knoll, an Industrial Light & Magic employee, who recommended Thomas turn it into a full-fledged image editing program. Thomas took a six month break from his studies in 1988 to collaborate with his brother on the program, which had been renamed ImagePro. Later that year, Thomas renamed his program Photoshop and worked out a short-term deal with scanner manufacturer Barneyscan to distribute copies of the program with a slide scanner; a "total of about 200 copies of Photoshop were shipped" this way.

During this time, John traveled to Silicon Valley and gave a demonstration of the program to engineers at Apple Computer Inc. and Russell Brown, art director at Adobe. Both showings were successful, and Adobe decided to purchase the license to distribute in September 1988. While John worked on plug-ins in California, Thomas remained in Ann Arbor writing program code. Photoshop 1.0 was released in 1990 for Macintosh exclusively.