Camouflage is a method of cryptic or concealing coloration that allows an otherwise visible organism or object to remain indiscernible from the surrounding environment through deception. Examples include a tiger's stripes and the battledress of a modern soldier. The theory of camouflage covers various strategies which are used.

Cryptic coloration in nature

The type of camouflage a species will develop depends on several factors:

• The environment in which it lives. This is usually the most important factor.
• The physiology and behavior of an animal. Animals with fur need different camouflage than those with feathers or scales. Likewise, animals who live in groups use different camouflage techniques than those that are solitary.
• If the animal is preyed upon, then the behavior or characteristics of its predator can influence how the camouflage develops. For example, if the predator has achromatic vision, then the animal will not need to match the color of its surroundings.

• Biochromes — natural microscopic pigments that absorb certain wavelengths of light and reflect others, creating a visible color that is targeted towards its primary predator.
• Microscopic physical structures, which act like prisms to reflect and scatter light to produce a color that is different from the skin, such as the translucent fur of the Polar Bear, which actually has black skin.

Cryptic coloration can change as well. This can be due to just a changing of the seasons, or it can be in response to more rapid environmental changes. For example, the Arctic fox has a white coat in winter, and a brown coat in summer. Mammals and birds require a new fur coat and new set of feathers respectively, but some animals, such as cuttlefish, have deeper-level pigment cells, called chromatophores, that they can control. Other animals such as certain fish species or the nudibranch can actually change their skin coloration by changing their diet. However, the most well-known creature that changes color, the chameleon, usually does not do so for camouflage purposes, but instead to express its mood.

There is a permanent co-evolution of the sensory abilities of animals for whom it is beneficial to be able to detect the camouflaged animal, and the cryptic characteristics of the concealing species. Different aspects of crypsis and sensory abilities may be more or less pronounced in given predator-prey pairs of species.