Original: The group, traditionally recognized as the suborder Lacertilia, is defined as all extant members of the Lepidosauria (reptiles with overlapping scales), which are neither sphenodonts (i.e., tuatara) nor snakes.
Simplified: When a display is needed, the lizards erect the hyoid bone of their throat, resulting in a large vertical flap of brightly colored skin beneath the head which can be then used for communication.