Photo manipulation is the application of image editing techniques to photographs in order to create an illusion or deception after the original photographing took place.  A mere enhancement or correction is known as retouching.
In digital editing, photographs are usually taken with a digital camera and input directly into a computer. Transparencies, negatives or printed photographs may also be digitized using a scanner, or images may be obtained from stock photography databases. With the advent of computers, graphics tablets, and digital cameras, the term image editing encompasses everything that can be done to a photo, whether in a darkroom or on a computer. Photo manipulation is often much more explicit than subtle alterations to color balance or contrast and may involve overlaying a head onto a different body or changing a sign's text, for examples. Image editing software can be used to apply effects and warp an image until the desired result is achieved. The resulting image may have little or no resemblance to the photo (or photos in the case of compositing) from which it originated. Today, photo manipulation is widely accepted as an art form.