Final answer:
Superficial and deep are terms used in anatomy to describe positions relative to the surface of the body. The skin is superficial to the muscles, and the heart is deep to the ribs.
Step-by-step explanation:
In anatomy, the term superficial refers to a position closer to the surface of the body, while deep refers to a position farther from the surface.
For example, the skin is superficial to the muscles, and the heart is deep to the ribs.