smoking is harmful to one's health,but why are there many smokers in the world?Answer it in English

At the outset,young men fill curious for smoking.They think this is a cool behavior.When they still are students,they get together and smoke.
From age,smoke have become a habit.They wrongly think smoking one cigarette after each meal ,it's better to be gods.Sometimes,smoking can relax mood and relieve stress when they are unhappy.and smoking also become a communicative means.Through a cigarette to strike up a conversation.
But smoking is harmful to health,whether smokers or passive smokers.Please don't smoke,for the health and happiness of ourselves and others.