The tnteraction in which one species benefits and other is neither harmed nor benefited.

An orchid growing as an epiphyte on mango branch.

Barnacles growing on the back of whale benefit while neither the mango tree nor the whale derives any apparent benefit.

The cattle erget and grazing cattle in close association, the erget always forage close to where cattle are grazing because the cattle, as they move, stir up and flush out insects from vegetation that otherwise might be difficult for the ergets to find and catch.

Sea anemone stinging tentacles and clown fish, fish gets protection from predators which stay away from the stinging tentacles, anemone does not get any benefit or is not harmed.