Nicotine is an organic compound, an alkaloid found naturally throughout the tobacco plant, with a high concentration in the leaves.
In small doses nicotine has a stimulating effect, increasing activity, alertness and memory. Repeat users report a pleasant relaxing effect. It also increases the heart rate and blood pressure and reduces the appetite.
Think all nicotine has deleterious effects on the human body? Not the mechanistically-slapped-together Nicotine Molecule from Digital Militia!