Smoking is harmful or benificial?

There are a great number of people getting into the habit of smoking, which has always been one of the hot topics that everyone is debating. It's clear that this habit has its negative and possitive effects on both smokers and society.
Smoking is considered to be a bad habit greatly effecting smokers' own health and their social lives. Firstly, lifelong smokers are bound to have a shorter life expectancy due to chronic diseases caused by smoking such as lung cancer, emphysema and heart attacks. In addition to the health aspect, smokers are thought to be unsociable. Not only do they make people in the vicinity annoyed with the cigarette smoke that is unpleasant to inhale, but they also pose the risk to others' health problems. Studies have shown that prolonged contact with passive smoking can cause lung problems. Finally, smoking costs a lot. For instance, a heavy smoker spend thousands of dollars annually on this habit.
Despite the warning given by docters and social psychologists about the ill-effects of smoking, people continue to smoke for a variety of reasons. Smoking is believed to improve concentration and help them think more clearly, especially in mental activities. It is also thought to be able to relieve stress and aid relaxation. For one thing, smoking is a sociable activity for those who do it. In some meetings, offering a cigarette is one of the best ways to start a converstion and create a friendly environment.
In conclusion, smoking is definitely harmful to community, yet it has some certain benefits. In my opinion, people should break this bad habit because they face much more serious problems than the benefit they get from smoking.