Trilobites are arthropods belonging to the order Tetraodontiformes in the phylum Arthropoda. The body is divided into three parts: head, chest, and abdomen; There is a carapace on the back, which is longitudinally divided into three pieces. The head is covered with a hard shell, called a cephalothorax; The central raised part of the head armor is called the head saddle, and the shape and size of the head saddle vary greatly depending on the type; The anterior part of the head saddle is the skull, on which there are eyes; There are also shells wrapped around the abdomen and tail. Named after the longitudinal division of the carapace on the back into three pieces. Widely distributed in ancient oceans, fossils are found on all continents today. I like to live in warm shallow sea areas and feed on algae, protozoa, and other organisms.