Smoking is a practice where a substance, most commonly tobacco, is burne and the smoke tasted or inhaled. This is primarily done as a form of recreational drug use, as combustion releases the active substances in drugs such as nicotine and makes them available for absorption through the lungs. It can also be done as a part of rituals, to induce trances and spiritual enlightenment. The most common method of smoking today is through cigarettes, either industrially manufactured or rolled with loose tobacco and a rolling paper. Other forms, though not as common, are pipes, cigars, hookahs and bongs.