It's one of the many cigarette smoking facts that they are dangerous for your health and the people around you. Among the dangers of smoking are lung cancer, nicotine addiction which in a worst case scenario can result in increased blood clotting, joint pain, increased blood pressure, tachycardia and so on.
Most people know these cigarette smoking facts among which is that cigarettes ultimately kill but they still smoke, why?
Well it isn't the same thing for everyone but usually smoking starts with peer pressure, everyone does it so you start as well, you want to belong to a group so you "have" to do it. Most likely you won't like it on the first try, but you again meet those smokers and you smoke again and you dislike it less and by the third smoke you start liking it.
Since you like it now you do it regularly and that's when the addiction starts. Nicotine addiction is one that's very hard to break because of the effect it has on our brain it keeps us calm. The other thing that's addictive specifically about the cigarette is that you have something in your hand, a lot of people start biting their nails when they're trying to quit smoking.
Another one of these interesting cigarette smoking facts is that 80-90% (80% in women, 90% in men) of the lung cancer deaths are a result of smoking. Most people wouldn't admit this usually they don't have a lot of compassion for people with lung cancer. They figure that it's their own fault, they smoked even though they knew that it has it's dangers they got cancers and they deserve to die. You will usually find a lot of more compassion for people with any other kind of cancer than lung cancer specifically because usually smokers get it.