Final answer:
Pill bugs are covered by an exoskeleton made of chitin, which includes a water-resistant exocuticle and a thicker endocuticle for support.
Step-by-step explanation:
The body of pill bugs, also known as woodlice, is primarily covered by an exoskeleton. Similar to insects and other arthropods, pill bugs have an exoskeleton made of a substance called chitin. This hard outer shell consists of two layers: the exocuticle and the endocuticle. The exocuticle is a thin, waxy layer, which is water-resistant, providing the pill bugs with protection against dehydration. The endocuticle underneath is significantly thicker, giving structural support to the bug. As seen in many arthropods, the body is segmented and organized into three main parts: the head, the thorax, and the abdomen.