Pigmentation mainly includes freckles, chloasma and seborrheic keratosis, etc. Patients with freckles will have pinpoint-sized brown spots, patients with chloasma will have brown patches, and patients with seborrheic keratosis will have flat papules and other symptoms. 1. Freckles: they occur on the face, and the typical lesions are light brown to brown pinpoint to rice grain-sized spots, round, ovoid or slightly irregular in shape, scattered in distribution, not fused with each other, and the number varies. 2. Melasma: the lesions are often symmetrically distributed on the cheeks and cheeks of the face and are butterfly-shaped. The lesions are yellowish brown or brown patches with different sizes and clear edges, and the pigmentation deepens after sun exposure. 3. Seborrheic keratosis: Seborrheic keratosis, also known as age spots, often occurs on the face, back of the hands, chest, back and other places. The lesions are characterized by one or several yellowish or light brown flat papules or plaques that are slightly higher than the skin surface, generally <3cm in diameter. Different symptoms of pigmentation are different, and pigmentation will have other symptoms, so it is suggested that patients should go to the hospital to find out the specific causes and then treat them.