Competition
Competition is when two or more organisms contesting for the same resource. For example, a silver Gull may compete with a pelican for food (fish)
Commensalism
Commensalism is when one organism benefit from the interaction while the other is nor harmed or helped. For example, a Fait tailed dunnart could use bushes and low lying vegetation to hide from predators however the vegetation is unharmed.
Mutualism
Mutualism is when two organisms work together and both benefit from each other. For example, parrots eats berries and fruits that can help spread seeds from plants and vegetation to help them reproduce.