There are various types and uses of charcoal as an art medium, but the commonly used types are: Compressed, Vine, and Pencil.
Compressed charcoal (also referred as charcoal sticks) is shaped into a block or a stick. Intensity of the shade is determined by hardness. The amount of gum or wax binders used during the production process affects the hardness, softer producing intensely black markings while firmer leaves light markings.
Vine charcoal is a long and thin charcoal stick that is the result of burning sticks or vines in a kiln without air. The removable properties of vine charcoal through dusting and erasing are favored by artists for making preliminary sketches or basic compositions. This also makes vine charcoal less suitable for creating detailed images.
Charcoal pencils consist of compressed charcoal enclosed in a jacket of wood. Designed to be similar to graphite pencils while maintaining most of the properties of charcoal, they are often used for fine and crisp detailed drawings, while keeping the user's hand from being marked.
Other types of artists' charcoal such as charcoal crayons were developed during the 19th century and used by caricaturists. Charcoal powders are used to create patterns and pouncing, a transferring method of patterns from one surface to another.