From a small tree called curry. Its leaves are aromatic and used as a spice in Indian cuisine.
Curry leaves have a light, slightly nutty and grassy flavor, used in many South Indian curries and vegetable dishes.
Curry leaves have an understated, subtle, flavor. Not to be confused with curry powder, which is a blend of many spices, curry leaves are light and delicate. While they are sometimes an ingredient in curry powder, they are not strong enough to bring curry flavor to a dish when used alone. Curry leaves are popular in the cuisine of Sri Lanka and Southern India, and are sometime used in cooking in Northern India. These light leaves immigrated with Southern Indian immigrants to South Africa, Malaysia and Réunion, and are sometimes found in the cuisines of those countries. They are often used as an herb, similar to bay leaves, though as they are soft they need not be removed before serving.