Puffing is a technique to bring smoke (usually tobacco) into the mouth cavity. This is achieve by sucking deeply on the filter end of a cigarette, allowing smoke to flow into the smoker's mouth before being inhaled into the lungs. One hereby produces a negative pressure, so that the smoke arrives at the mucous membranes and to the taste receptors. In this way, nicotine is absorbed, and the flavors in the tar particles can be tasted.