Testudines is an order of reptiles that includes turtles, tortoises, and terrapins. These creatures are known for their unique shells, which provide protection from predators. The shell is made up of two parts: the upper part called the carapace and the lower part known as the plastron. Testudines can be found in various habitats, from oceans to freshwater rivers and even on land. These reptiles are fascinating for their longevity and slow growth. Many species of turtles and tortoises can live for several decades, with some even reaching over a century. Testudines are also important for their ecosystems, as they help maintain the balance of their environments by grazing on vegetation and controlling insect populations.