There's a thick layer with interlocking scales (called scutes) and bony buttons or plates (called osteoderms) that create an armor for protection. The coloration in the crocodile's skin allows it ...

A bony plate of armor called an osteoderms from the trunk region of Garzapelta muelleri. Top image is the osteoderm as seen from above. The bottom image is the osteoderm seen from the side.

Crocodilians—semiaquatic reptiles comprising crocodiles, gharials ... Crocodilians are also equipped with osteoderms, which are essentially bony deposits covered by their scutes.