Introduction The skin is the largest organ of the body weighing between 2 and 4.5 kg (16% of body weight) and covering approximately 2 m
2 (Tortora and Derrickson, 2006). The skin is between 1 and 2 mm thick, depending on the part of the body that is being considered. It is dynamic and changing, capable of healing itself and responding to the external environment in such a way that ensures human survival. Like all other organs, the skin is capable of failure, the results of which can be physically and psychologically debilitating and potentially lethal.
To understand how to care for the skin, it is necessary to have an understanding of skin biology. Therefore this section will cover:
- Skin structure and function;
- Skin changes from pre-birth to old age;
- Ethnic differences.
