Photo imaging, also known as image editing, retouching, image manipulation, or colloquially as "Photoshopping," is the process of altering images. It can be done with modern digital techniques or with traditional analog processes.Know More
Photo imaging was traditionally accomplished with tools such as an airbrush, but in modern times it is done via advanced computer software. The most popular program by far is Photoshop, which is why many refer to the process of altering images as "Photoshopping." However, Photoshop is not the only software available.
These programs can accomplish relatively simple effects such as altering contrast or brightness, cropping the frame and distorting or resizing the image, but they are also capable of more advanced processes such as lens correction, selective color changes, perspective changes, sharpening or softening the image, selecting and merging, changing the color depth, gamma correction and more. Thus, the image can be lightly edited or "fixed", but it can also be completely changed, presenting a composite or otherwise "fake" image throgh extreme editing.
Besides Photoshop, there are several other photo imaging programs, including GIMP, Pixlr, Paint.NET and PicMonkey. Some are free but others can cost up to several hundred dollars. The functions of each piece of software will vary.