wall of a fruit, developed from the ovary/carpel wall

Many seed plants have edible fruit. The part of the fruit outside the structure which contains the seeds, is called pericarp. Very often it corresponds to the part of the fruit that is eaten.

Schematic of a peach: the part labeled in green is the seed, those labeled in orange the pericarp.
A peach cut open. The yellow part outside the kernel is the pericarp.