Photoshop

Photoshop is a software package from Adobe Systems, Inc., that allows users to manipulate digitized photographs; the software can be used to enhance quality, create original pieces of artwork, add text and shapes, and apply professional-quality special effects to digital images. Photoshop was one of the first programs to give users the ability to extensively manipulate graphics on a computer.

In 1987, Thomas Knoll, a Ph.D. student in computer vision at the University of Michigan, wrote a program called Display that would allow for gray-scale images to be displayed on the black-and-white monitor of his Macintosh computer. Thomas' brother John was an employee at Industrial Light and Magic, and he was intrigued by the possibilities of his brother's work. He encouraged Thomas to continue working on the program, this time using a Macintosh II with a color monitor, and to enable the program to be able to save the images in varying formats. Thomas changed the name from Display to ImagePro for commercial applications, then later to Photoshop due to trademark.

By 1988, John had struck a deal with BarneyScan Corporation (later to be incorporated into PixelCraft, Inc., a division of Xerox), a leading producer of image scanners and creator of the first desktop slide scanner, to include a limited amount of bundled software with their scanners. Eventually, a demo version of Photoshop was presented to Adobe, which agreed to buy the rights to Photoshop in 1989. The first version, Photoshop 1.0, was released to the public in 1990. Photoshop was available only to Macintosh users until Adobe released Photoshop 2.5, a Windows-based version, in 1993. In 2000, Adobe released Photoshop's most updated version, 6.0, which is targeted specifically toward Web designers and publishers.

Photoshop allows adjustments to be made to a photo's hue, saturation levels, contrast, and brightness, as well as the elimination of red-eye, to name a few basic features. The software also affords its users more advanced features, such as layers, filters, and masking techniques that make complex operations easy, making it the photograph-manipulation program preferred by photographic and graphic-design professionals. Photoshop is also compatible with all other Adobe graphics programs, and allows users to export their files into varying file formats.

A signature feature of Photoshop is the concept of layers, which can best be described via a comparison to cartoon animation. Users of Photoshop start with a background image, much like a cartoon animator does. When objects or text need to be added, users can create transparent layers for each object, as when cartoon animators place a clear cellophane sheet bearing its own image onto the background to add an object or character to the picture. In Photoshop 6.0 and later versions, unlimited numbers of layers can be stacked on top of each other to create a desired effect. Users can then experiment with different colors, objects, and text without affecting the overall picture, simply by turning layers on and off, or delete a layer that is no longer necessary without deleting all of their other manipulations.

As with all software programs, there are drawbacks. One of the difficulties presented by older versions of Photoshop was the inability to undo more than one command on the current layer that a user is working on. More recent versions include a history section, which tracks user changes and allows users to undo as many functions as necessary.

...