The respiratory system is the network of organs and tissues that help you breathe. It includes your airways, lungs, and blood vessels. The muscles that power your lungs are also part of the respiratory system. These parts work together to move oxygen throughout the body and clean out waste gases like carbon dioxide. There are many methods of respiration used by different organisms to inhale oxygen and exhale carbon dioxide. Unicellular and simple celled organisms use the method of diffusion. Animals have a complex respiratory system for the exchange of gases. Fishes use gills to absorb oxygen. Insects have a respiratory system that consists of spiracles and tracheae. The two types of respiration are Aerobic Respiration and Anaerobic Respiration. Both types of respiration are discussing here.