A mole is a small, often slightly raised blemish on the skin, made dark by a high concentration of melanin. The scientific name for moles is melanocytic naevi.
Spread of pigment from the border of a spot into surrounding skin.
The genes we inherit from our parents, along with the amount of sun to which we are exposed (especially during childhood), are major factors in determining mole numbers. Skin with more sun exposure tends to have more moles. However, moles may also occur in sun-protected areas like the palms, soles, and genitals.
The skin should be checked every few months for any new moles that develop (particularly after teenage years, when new moles become less common), or any changes to existing moles. A mole can change in a matter of weeks or months.
Moles usually target more individuals with fair skin. They usually respond to hormonal changes such as women during pregnancy whose moles may get darker, teenager's moles usually increase in number and older individuals often have moles that disappear.