Heated tobacco products (HTPs) are tobacco products that heat the tobacco at a lower temperature than conventional cigarettes. These products contain nicotine, which is a highly addictive chemical. The heat generates an aerosol or smoke to be inhaled from the tobacco, which contains nicotine and other chemicals. HTPs may also contain additives not found in tobacco, including flavoring chemicals. HTPs generally heat tobacco to temperatures under 600 °C (1100 °F), a lower temperature than conventional cigarettes. There are three general types of heated tobacco products: one that immediately heats processed tobacco to generate aerosol, another that uses processed tobacco that is heated in (but not generate) an aerosol, and one where the processed tobacco gives flavor to the aerosol as the latter moves over the former. Some heated tobacco products heat specially-designed sticks, plugs, or capsules containing tobacco, while others work by heating liquids that create an emission that then passes through a tobacco plug to absorb flavor and nicotine from the tobacco. Heated tobacco products are still new, and scientists are still learning about their short- and long-term health effects. The emissions created from heated tobacco products generally contain lower levels of harmful ingredients than conventional cigarettes.