Blue Crab Molting
A major problem with an exoskeleton is that it can not expand to allow growth. Therefore, growth occurs in “steps”. At certain stages, the animal climbs out of its old exoskeleton, expands, and grows a new one. The process is referred to as “molting”. The following is a video of a blue crab molting. https://www.shapeoflife.org/video/arthropods-blue-crab-molting
Cicada emerging from its nymph (immature) stage
In some insects, the last molt includes metamorphoses. The adult insect that emerges is vastly different from the nymph that it grew out of. The cicada is an example.