Chilli peppers are fiery because of a substance called capsaicin. The hotter the pepper, the more capsaicin it contains. Studies show that the capsaicin in chilli peppers causes the body to release endorphins, which can give a person a feeling of well-being or pleasure.
Scoville units measure the intensity of chilli peppers. They are measured in multiples of 100, beginning with bell peppers at 0 and ending with habaneros at 300 000 units. Much of the flavour found in a pepper resides in their flesh while the heat they possess live in the seeds and membranes. Removing these will allow you to enjoy the flavour while reducing the fire of these piquant pleasures. It's very important to always wear disposable gloves when working with chilies. Discard the gloves after use and wash your hands thoroughly. Whatever you do, don't touch your eyes!!
Some of the more common chilies found in your local grocery store include: