I always thought smoking tobacco was an unpleasant and extremely harmful habit. This is partly because I personally suffered greatly from exposure to secondhand smoke while growing up. Furthermore, many people, including certain family members, had been struck by smoke-related diseases or passed away due to lung cancer.In this brief, I tried to inform readers who may not be aware of the severe diseases caused by smoking in simple words. I am hopeful that through reading this brief, people will think twice before lighting up a cigarette.