This document discusses the history and health effects of smoking. It begins with the origins of tobacco use among Native Americans and its spread to Europe. It then discusses the addictive properties of nicotine and how cigarettes effectively deliver nicotine to the brain. The document outlines the various health risks of smoking such as increased risk of lung cancer, COPD, and heart disease. It also discusses challenges with smoking cessation and methods that can be used to help people quit smoking such as nicotine replacement therapies, bupropion, and varenicline. The document concludes by discussing approaches to harm reduction for smokers unable or unwilling to quit.