Skin lesions can be divided into two main types: primary and secondary. Primary skin lesions originate on previously healthy skin and are directly associated with a specific cause. Common examples of primary skin lesions include freckles, moles, and blisters, among others. On the other hand, secondary skin lesions develop from the evolution of a primary skin lesion, either due to traumatic manipulation, such as scratching or rubbing, or due to its treatment or progression. Examples of secondary skin lesions include crusts, sores, ulcers, and scars.