A Scoville unit is used to specify the hotness of a food, specifically chili peppers. In 1912 Wilbur Scoville, devised a system to determine how hot foods are. He used a panel of tasters to provide heat scores for different peppers. Although we still use Wilbur's name for the unit, the current method is much more scientific.

The sensation of heat that we experience from eating certain peppers is due to a chemical called capsaicin. The more capsaicin present in a pepper, the hotter it will taste.

As shown on the table below, Scovilles vary widely from one pepper to the next. There are also variations of heat from one pepper to the next within the same species; growing conditions, soil and other factors have an affect on the amount of capsaicin within a given pepper.