Skin explained

The Epidermis
 This top-most layer of skin functions as the protective shield for the body. It consists of 5 very thin layers, the most superficial one being the corneum. This is where the initial signs of aging and UV damage are visible. The cells in the epidermis are renewed naturally every 15-30 days and contain pigment producing cells, sweat pores and hair shafts. 

The Dermis
This layer of skin provides structure and support. It is a thicker layer of skin, consisting of 2 layers: the papillary and reticular layers. This deeper and thicker layer of skin contains both the hair follicles, sweat glands and vessels. In this layer, we see more significant signs of aging and solar damage, normally in the 30-40 yr old age range. 

The Hypodermis
This deeper layer of skin provides insulation and padding for the body. It contains loose connective tissue and fat. It also contains deeper and larger blood vessels and nerves than in the dermis.