Definition Of Commensalism
Commensalism is a relationship between two organisms where one organism benefits while the other one isn't affected.
Remora and the whale.
the Remora and whale are a good example because the Remora eats the left over food that the whale leaves behind and then hitches a ride with the whale.
Whales and barnacles are Commensalism because the barnacles attach themselves to the whale for filter feeding and a lot of people confuse that with parasitetism but it doesn't hurt the whale.
The habitat they live in
The whale lives in the ocean but mostly stay where the warm water is.
Barnacles inhabit rocky shores and exposures.
The Remoras habitats is in warm marine water like the whale