Invertebrata, or invertebrates, are animals that lack a backbone or spinal column. This diverse group includes organisms such as insects, sponges, jellyfish, and octopuses. Invertebrates make up about 95% of all animal species on Earth and can be found in various habitats, from deep oceans to forests. Invertebrates are classified into several major groups, including arthropods, mollusks, and cnidarians. They play essential roles in ecosystems, such as pollination, decomposition, and serving as food for other animals. Their adaptability and variety contribute significantly to the planet's biodiversity.