Which type of burn affects only the outer layer of skin?

First-degree burns are classified as superficial burns that affect only the outer layer of the skin, known as the epidermis. These types of burns typically result in redness, minor inflammation, and pain, similar to a mild sunburn. The superficial nature of first-degree burns means that they generally heal quickly, often without the need for medical treatment, and typically do not result in any scarring. They are characterized by intact skin, and while they can be uncomfortable, they are the least severe of burn classifications.

In contrast, second-degree burns extend deeper into the skin, reaching the dermis and resulting in blisters and more significant pain. Third-degree burns penetrate through all layers of the skin and can cause damage to underlying tissues, often resulting in a charred appearance and loss of sensation in the burned area. Electrical burns vary widely in severity, often depending on the current's path through the body and can cause deep tissue damage even if the surface appears unburned.