A symbiotic relationship is a bonding between two different species of organisms often over a long period of time. The relationship itself can be mutualistic, parasitic, or commensal in nature.

Mutualistic relationship is where both the organisms are benefited by the bonding. Parasitic is where one organism gets all the benefits and the other usually pays a price. Commensal is where one organism benefits but the other does not suffer any harm. Examples of mutualistic relationship is the formation of coral reefs where many types of coral organisms work together for the benefit of each other. Parasitic relationship is observed almost everywhere like worms in human intestines. Commensal relationship's example is crabs using shells to protect their bodies.