coal(The natural, rocklike, brown to black derivative of forest-type plant material, usually accumulated in peat beds and progressively compressed and indurated until it is finally altered in to graphite-like material)
activated carbon(A powdered, granular or pelleted form of amorphous carbon characterized by a very large surface area per unit volume because of an enormous number of fine pores)
charcoal(A porous solid product containing 85-98% carbon and produced by heating carbonaceous materials such as cellulose, wood or peat at 500-600 C° in the absence of air)