The areca nut is not a true nut, but rather the seed of a fruit categorized as a berry. It is commercially available in dried, cured, and fresh forms.
When the husk of the fresh fruit is green, the nut inside is soft enough to be cut with a typical knife. In the ripe fruit, the husk becomes yellow or orange, and as it dries, the fruit inside hardens to a wood-like consistency. At that stage, the areca nut can only be sliced using a special scissors-like cutter.