If you are a smoker, then you have three problems right now:
1) Nicotine is a highly addictive drug. The reason it is so addictive is because it rewires your brain. A recent post puts it this way: "Once rewired, your brain feels bad without nicotine. This happens because nicotine mimics a neurotransmitter called acetylcholine. To your neurons, nicotine looks like a surge of acetylcholine. This surge causes a release of dopamine, which is pleasant and feels good. Unfortunately, your brain also responds to the surge by changing the number of acetylcholine receptors and the amount of the neurotransmitter that it releases. When you stop smoking, the lack of nicotine causes an imbalance, and you feel bad. Very bad. So you start smoking again. The only way to beat cigarettes is to cut your consumption of nicotine long enough (either cold-turkey or by ramping it down) to let your brain re-rewire itself back to normal (takes several weeks cold turkey)." For more info see How Nicotine Works and How does your body digest a cigarette?.
2) So you are addicted to nicotine. And you are using cigarettes as the delivery system for the nicotine you need. The problem with cigarettes is that they are poisonous. The nicotine arrives in a puff of smoke, and the smoke causes cancer, emphysema, etc.
3) Because cigarettes are poisonous, non-smokers don't want cigarettes around. So you and your cigarettes have been kicked out of the building and must now smoke outdoors. This can be unpleasant in winter or the heat of the summer, and it also wastes time.
Therefore, many smokers are looking for a different delivery system for the nicotine they need. They may be doing that simply to avoid the trip outdoors. Or they might want to lower the cancer risk. Or they may be trying to gain more control over nicotine intake so they can ramp it down to zero over time.
There are currently several alternatives for nicotine delivery, including patches, gum, inhalers and even nicotine water. But many smokers are getting excited about the latest craze: electronic cigarettes, AKA eCigarettes. An eCigarette is an electronic device that delivers nicotine as a mist. You can see the eCigarette in action here:
The only problem with eCigarettes right now is the lack of testing. They are new, and no one really knows what to do with them from a regulation standpoint until they are tested:
Makers of e-cigs tout their product as the first healthy cigarette, free of harmful chemicals and tar typically found in tobacco products. The only ingredient: pure liquid nicotine. "Our product is comparable to the nicotine patch except people still get the oral fixation, which they love," explained Elicko Taieb, CEO of Smoking Everywhere, one of the largest distributors of electronic cigarettes.
But the U.S. Food and Drug Administration considers e-cigs an unapproved new drug because of a lack of scientific proof that they're safe or effective. The FDA is trying to halt importation of e-cigs, but isn't seizing products already being sold in the United States.