Photoshop is a computer program for raster image editing, published by Adobe. It is a very popular tool among graphics designers with Apple Macintoshes and Wintel PCs.
The development of Photoshop started in 1987 by the brothers Thomas and John Knoll, although it was not until 1990 that the program was first released by Adobe. Remarkable was that the program was intended from the start as a tool for manipulating images that were digitized by a scanner.
Although mainly suited to edit images for printing, Photoshop is being used increasingly to produce images for the World Wide Web.