picture description: This his a picture of a human hand holding a cigarette.  Cigarettes are a delivery system for a drug called nicotine.  Nicotine is highly addictive, more so than heroin.  It makes humans feel better and relax.  Humans also use cigarettes to engage in social bonding.  They administer the nicotine by setting fire to the distal end of the cigarette, then inhaling the smoke from that fire through the proximal end.