Raster graphics editor

A raster graphics editor is a computer program that allows users to create and edit images interactively on the computer screen and save them in one of many popular "bitmap" or "raster" formats such as JPEG, PNG, GIF and TIFF.

A raster graphics editor supports a certain repertoire of image editing operations. Depending on the program, the capabilities may be extended by use of plug-in software.

Some editors specialize in the editing of (digital) photographs, such as Adobe Photoshop or RawTherapee, while others are more geared to artist-created illustrations, like Adobe Fireworks.

An image viewer program is usually preferred over a raster graphics editor for viewing images.

Comparison to vector graphic editors

Vector graphics editors are often contrasted with raster graphics editors, yet their capabilities complement each other. The technical difference between vector and raster editors stem from the difference between vector and raster images. Vector graphics are created mathematically, using geometric formulas. Each element is created and manipulated numerically; essentially using Cartesian coordinates for the placement of key points, and then a mathematical algorithm to connect the dots and define the colors.