If you are a smoker, be aware that your chances of landing a job will be diminshed.
1. Most people today do not smoke, so chances are the person interviewing you is a non-smoker.
2. Most non-smokers react negatively to being around smokers.
3. All of the medical statistics indicate that smokers take more time off work (sick-days) than non-smokers.
4. If you are applying for a job, you will not be the only person interviewing for it.
The result: 1+2+3+4 = the employer has choices. You draw the conclusion. If you smoke, you give the employer a reason not to pick you. There are of course more profound reasons to not smoke.