The class Insecta, belonging to the phylum Arthropoda, represents a highly diverse group of animals characterized by segmented bodies, jointed appendages, and an exoskeleton made of chitin. The body of insects is bilaterally symmetrical and is divided into three distinct regions: head, thorax, and abdomen. The head bears sensory and feeding structures, the thorax is primarily involved in locomotion, and the abdomen mainly contains digestive, excretory, and reproductive organs. The head of an insect is typically fused and bears a pair of compound eyes, which are composed of numerous ommatidia allowing a wide field of vision and sensitivity to movement. In addition, there are usually three simple eyes called ocelli, which are light-sensitive organs that help in detecting changes in light intensity. The head also carries a pair of segmented antennae that serve as important sensory organs for touch, smell, and sometimes hearing. The mouth parts of insects are highly specialized and show remarkable adaptations depending on their feeding habits.