A classification within the biological sciences that encompasses small, typically air-breathing creatures characterized by segmented bodies, jointed limbs, and a chitinous exoskeleton, which also includes references to amphibian species and amphibians in general, a diverse and distinct group of cold-blooded vertebrates constituting the class Amphibia. This category further extends to all arthropods, an invertebrate animal of the large phylum Arthropoda, and broadly covers all creatures within the animal kingdom.