Botanically speaking, cashew are not actually nuts but merely seeds. Culinary uses for cashew seeds are similar to uses for nuts, however, and the seeds are frequently referred to as nuts. Cashews, unlike oily tree nuts, contain starch to about 10% of their weight. This makes them more effective than nuts in thickening water-based dishes such as soups, meat stews, and some Indian milk-based desserts. Many Southeast Asian cuisines use cashews for this unusual characteristic, rather than other nuts.
Cashew nuts are commonly used in Indian cuisine, whole for garnishing sweets or curries, or ground into a paste that forms a base of sauces for curries (e.g., korma), or some sweets (e.g., kaju barfi). It is also used in powdered form in the preparation of several Indian sweets and desserts. In Goan cuisine, both roasted and raw kernels are used whole for making curries and sweets.
The shell of the cashew seed yields derivatives that can be used in many applications from lubricants to paints, and other parts of the tree have traditionally been used for snake-bites and other folk remedies.
Originally native to northeastern Brazil, the tree is now widely cultivated in Vietnam, Nigeria and India as major production countries.