Charcoal is defined as dark grey residue consisting of impure carbon obtained by removing water and other volatile constituents from animal and vegetation substances  or a black grey form of carbon, produce by heating wood or other organic substances in enclosed space without air.
Charcoal is basically composed of tiny particles or carbon which is usually produce by slow pyrolysis, heating of wood, sugar, bone char, or other substances in the absence of oxygen resulting in soft, brittle, lightweight, black, porous material which resembles coal and is about 50 percent to 95 percent of carbon.
The traditional way of producing charcoal is ‘the Kiln process’ is normally associated with huge amount of smoke which is a major contributor to the depletion of ozone layer but with the help of Orin Stafford, who helped Henry Ford established his briquette business developed an alternative method of producing charcoal in the early 1900s called the retort method.
The retort method involves passing wood through a series of hearths or oven. It is a continuous process wherein wood constantly enters one end of a furnace and charred material leaves the other. Virtually no visible smoke is emitted from a retort, because the constant level of output can effectively be treated with emission control device such as afterburners .
Charcoal could be found in several forms which include activated charcoal, lumps, extruded charcoal and briquette.
Activated charcoal is a kind of charcoal with higher carbon composition, is made at elevate temperature in a chamber where air and oxygen are pumped out to ensure fewer impurities.
The lump charcoal is made directly from hardwood material and usually produces far less ash than briquette.
The extruded charcoal is which is made by extruding either raw ground wood or carbonized wood into logs without the use of binder. The heat and pressure of the extruding process holds the charcoal