Common name for Capsicum plants of the Solanaceae (nightshade) family, grown for their fruit. As with tomatoes (also Solanaceae) the fruit pods are usually classed and cooked as vegetables, although they are technically fruit.
Chilis are noted for their capsaicin content (an oil which gives the sensation of burning although it does not produce a chemical burn), and many gardeners and cooks use chili peppers solely for their capsaicin. However, this is a diverse group with well over a hundred cultivars producing a range of flavors that also include sweet (no capsaicin) peppers such as bell peppers, and mild/moderate chili peppers (e.g. Anaheims).