Smoking is a very bad habit, one I was lucky enough to kick. Tobacco anyway. I am here to answer your questions 
I'm glad you kicked the habit. What made you quit?
I think the fact that I knew it was so unhealthy, and it smells bad. It contains over 50 chemicals, and those not only hurt your health, but also stain your teeth. 
Gross.  Yes, I thinking I would be worried about cancer with smoking.  Was that on your mind?
It was, but I never thought I would smoke long enough for that. I thougth more about how there was a mix of aerosol particles and gasses all mixed together.
I didn't know that.  How long did you smoke?
For about 2 or three years. It was easy to quit knowing the negative health effects to my respiration.