An image with an empty or featureless background. Commonly, a background that is solid white, transparent, or another color.
An image with a simple background takes place in an empty void, with no identifiable setting or location. This is opposed to an image that takes place in an identifiable setting, such as indoors or outdoors, or at day or night.
As a rule of thumb, there is nothing to tag in the background. Another rule of thumb is that the subject could easily be placed on a different background.
Simple colors and patterns, such as gradient backgrounds, grid backgrounds, striped backgrounds, etc, may also be considered simple backgrounds.
