^
What he said about quitting smoking is so true. If you've been doing it long, you'll see improvements in breathing after stopping. Just a healthier feeling all around.
I noticed that I started coughing a lot more for a while after I quit smoking. There is a biological reason for this: Nicotine and other things in the smoke temporarily paralyze the cilia of lung cells that carry out the gunk. It builds up and when the system starts working properly again you'll cough up a lot of black stuff. I couldn't believe what kept coming up after I quit. I don't want to smoke cigarettes again. Too addictive and harmful and not many benefits to smoking.
Good for you and anyone else who has or is trying to quit. If you are thinking of quitting, give it a shot - when you succeed you will feel better and you'll be glad you quit. Eventually, other people smoking won't make you think about smoking if you are like me. Most people are able to quit but only when they actually want to quit or they care about their health and staying alive.