Scars are the result of excessive proliferation of collagen fibers caused by skin injuries during the healing process. There are many causes of scars, and different types of scars can result from different causes of trauma. So, what are the types of scars? Scars can be classified into the following types based on their histological form and morphological distinction 1. Superficial scars formed after light abrasions on the skin, or due to superficial II degree burns, or superficial infections on the skin, usually involving the epidermis or superficial dermis. The clinical manifestation is slightly different from normal skin in appearance, with rough surface or pigmentation changes, flat and soft localization, and generally no functional disorder, and the scars will gradually become less obvious with time, so no special treatment is needed. 2.Proliferative scars Where the injury involves the deep dermis, such as deep II degree or above burns, cutting wounds, infections, the donor area after cutting medium-thick skin pieces, etc., proliferative scars may be formed. The clinical manifestation is that the scar is significantly higher than the surrounding normal skin, with local thickening and hardening. In the early stage, the scar surface is red, flushed or purple due to capillary congestion. In this stage, itching and pain are the main symptoms, and the surface may even break down due to scratching. Symptoms are aggravated by increased ambient temperature, emotional stress, or spicy and irritating foods. Proliferative scars often last for months or years before undergoing gradual degenerative changes. The length of this proliferation period varies depending on the person and the location of the lesion. 3.Atrophic scars occur in patients with large third-degree burns, after healing of long-term chronic ulcers, and after electric shock injuries to areas with less subcutaneous tissue, such as the scalp and anterior tibial area. The damage is usually severe, involving the whole skin and subcutaneous fatty tissue. Clinical manifestations: scars are hard, flat or slightly above the skin surface, and closely adherent to deep tissues such as muscles, tendons, and nerves. The scars have extremely poor local blood circulation and are light red or white in color. The epidermis is extremely thin and cannot withstand external friction and weight-bearing, so they can easily break down and form chronic ulcers that do not heal. If it is healed for a long time, there is a possibility of malignant transformation in the late stage, and it is mostly squamous epithelial carcinoma. Atrophic scars have great contractility and can pull the neighboring tissues and organs, causing serious dysfunction. 4.Scars Scars are essentially a kind of connective tissue tumor on the skin, and are scars characterized by persistent and strong proliferative force, the occurrence of which has obvious individual differences.