A wound in the medical sense is a loss of tissue in the skin or in the tissue under the skin.
There is therefore a "pit", crack or immersion in the skin.
The wound may bleed or form a crust or coating.
If there is an infection in a wound, it will be fluid, red and more painful.
Ulcers on the calf result from poor blood supply to an area of the skin, and the reason for this can be swelling of the leg, smoking, disease in blood vessels or diabetes.
Leg ulcers typically occur at the bottom of the leg in older people with swelling ("thickening") of the leg.
Diabetic ulcers typically occur on the foot.
Skin cancer of the basalioma type quite often causes crusted sores on the face or body.
A number of skin diseases can cause ulcers in the skin.
First you have to find out what kind of wound it is.
In the case of leg ulcers, it will often help to reduce the swelling in the leg, for example with a compression stocking or by keeping the leg elevated.
Many times bacterial samples or tissue samples must be taken from the wound, before the treatment is decided.
A superficial wound can heal without scarring, while deeper wounds in the skin will lead to scarring.