Epidermis: This layer is made of skin cells at the end of their life-cycle. These cells provide protection from injury and a barrier to keep infectious organisms at bay. Think of this layer as the mulch covering the flowerbed. The epidermis holds in fluid and protects raw nerve cells from too much stimulation.
Dermis: The top soil. This layer contains capillaries that feed the cells with nutrient-rich blood. Just like top soil, most things grow here - including hair follicles, nerve cells, and sweat glands. If damaged, the dermis will weep serous fluid and swell.
Subcutaneous: The subcutaneous layer is also known as the hypodermis, and it is technically not officially skin, but rather attaches the skin to everything beneath. It also contains a layer of fat. Some of us have more fat than others, but this layer is always present in some form. In the flowerbed, this is the layer of sandy foundation that allows for drainage. Indeed, blood vessels in the subcutaneous layer feed and drain the capillaries of the dermis.