RGB or Natural Colour Imagery
Optical imagery collected by Satellite and airborne sensors is usually presented in one of two forms. The one form is referred to as Natural Colour imagery, often by its acronym, RGB imagery. This is because it refers to the bands that are used to create this imagery, namely the Red, Green and Blue bands. It is called Natural Colour imagery because these bands fall within the visible part of the spectrum, i.e. visible to the human eye. This imagery looks like normal colour photographs we are familiar with and are intuitive to our understanding. Thus, we can easily interpret the information contained in the imagery.
For example, we can easily distinguish between agricultural fields, grassland and forests, even different types of forest. Built-up areas and infrastructure such as roads are also easy to distinguish.