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What features do insects share with other arthropods?

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Illustration showing a variety of adult insects, each labeled with its common name and order, including walkingstick, earwig, stonefly, tree cricket, dragonfly, female scale, cat flea, thrips, sucking louse, thysanuran, ant, scarab beetle, stinkbug, mosquito, and cabbage butterfly, highlighting their diverse shapes and sizes. — insect An illustration of insect diversity.

Insects share several fundamental characteristics with other members of the phylum Arthropoda, which is the largest phylum in the animal kingdom. These shared features include:1

Exoskeleton: All arthropods possess a hard exoskeleton composed of chitin and protein. This structure provides support and protection, and it must be periodically shed through a process called molting (or ecdysis) to allow the animal to grow.213
Segmented Bodies: Arthropods are characterized by bodies divided into segments.21
Jointed Appendages: The name "arthropod" literally means "jointed feet." These organisms possess paired, jointed appendages that are specialized for various functions, such as walking, swimming, or burrowing.214
Muscular System: Muscles attach to the interior of the exoskeleton, functioning together as a lever system to facilitate movement.4
Nervous System: Their nervous system includes a dorsal brain and a ventral nerve cord.2
Absence of Cilia: Arthropods lack locomotory cilia throughout their life cycles, including during the larval stage.14