An arthropod is an invertebrate animal that belongs to the phylum Arthropoda. This group includes insects, arachnids (like spiders and scorpions), crustaceans (such as crabs and lobsters), and myriapods (like centipedes and millipedes). Arthropods are characterized by their segmented bodies, exoskeletons made of chitin, and jointed appendages, which allow for a wide range of movement. Arthropods are the most diverse group of animals on Earth, with millions of species identified. They can be found in nearly every habitat, from deep oceans to high mountains. Their adaptability and various life cycles contribute to their success in different environments, making them essential to ecosystems as pollinators, decomposers, and food sources for other animals.