The areca palm, cultivated in India, Sri Lanka, Thailand, Malaysia, and the Philippines, has a slender, unbranched trunk reaching 12 or 15 metres (40 or 50 feet) high and about 45 centimetres (18 inches) in circumference and is topped by a crown of six to nine very large, spreading, pinnate fronds. The fruit is about the size of a small hen's egg. Within its fibrous rind is the seed, or nut, the albumen of which is hard and has a mottled gray and brown appearance.

The fruits of the areca palm, gathered between August and November, before they are quite ripe, are husked, boiled in water, cut into slices, and dried in the sun, becoming dark brown or black.

For chewing, a small piece of the areca palm's fruit is wrapped in a leaf of the betel pepper, along with a pellet of shell lime or chunam to cause salivation and release the stimulating alkaloids. In some cases cardamom, turmeric, or another aromatic is added for flavour and stimulation. Chewing results in a copious flow of brick-red saliva, which may temporarily dye the mouth, lips, and gums orange brown. Contrary to general belief, the teeth of habitual chewers are not blackened by the betel juice, but chewers often artificially stain the teeth black. Betel nuts are a source of inferior catechu (q.v.); its chief alkaloid is arecoline, a drug used by veterinarians as a worming agent.