The Arthropoda is a phylum consisting of invertabrate animals with an external skeleton and a segmented body, also. They are mostly made of insects, arachnids, and crustaceans, however there are some more. They all move and breathe (sort of) in the same way (crawling mostly), however live in different environments, as we can see down below.
Spiders
Spiders are a common types of the Phylum Arthropoda that we see everyday. Their Respiratory System contains two organs that allows them to properly breathe - Book Lungs and Tracheae. Tracheae are very small tubes in which the spider can transport air to the different tissues in the body. There is an opening in front of the spinnerets called spiracles, in which the air enters through. The Book Lungs are in the cavities of the abdomen. Through a small slit, the air enters the cavities. Then, oxygen passes through the blood of the spider as it circulates in the lung. Thus, the spider can breathe and carry out everyday functions. Most spiders have only one lung, however there are some with two.
Crayfish
Crayfish are a type of fish that live in freshwater, and are related to the lobster family (a little smaller than lobsters, however). They are also referred to as crawdads and crawfish. These fish have an extremely odd way of breathing. Their gills are on the outside of the body (located somewhat between the carapace and body wall), however they are somehow attached to the legs of the fish, also! Therefore, the more it walks, the more it breathes. However, if it wants to, it can walk on land and breathe, because it has a small pocket within itself where it stores water when it needs it. The crayfish is a very unique fish in the Phylum Arthropoda, mainly because of the body structure and how it can breathe.
Bees
Many insects, including bees, have no lung(s) within their small bodies. However, they do have a system of trachea, which carry oxygen to all the cells, and carbon dioxide away from all the cells. They are connected by spiracles, like in spiders. While they are at rest and not flying or pollinating, respiration occurs by a process called diffusion. Although they're blood contains no hemoglobin, a molecule called cytochrome enhances the gas exchange throughout the small body of the bee. They also learned how to deal with high concentration of carbon dioxide, much better than humans ever could!