Arthropods (phylum Arthropoda) are members of a large phylum of animals. The word "arthropoda" means jointed legged, so evidently all arthropods are jointed legged. All arthropods also have exoskeletons made primarily of a
hard protein called chitin. Arthropods are grouped into the insects, arachnids, crustaceans, and myriapods. Insects are a class of arthropod with
three body segments - the head, the thorax, and the abdomen. Arachnids and crustaceans have the head and thorax combined into
one --- this is known as the cephalothorax. However, arachnids do not have antennae, but crustaceans have a
set of antennae and another
set of shorter antennules. Myriapods are the subphylum with the centipedes and millipedes. Their
bodies are divided into A LOT OF SEGMENTS!!!!