- A nut is a hard-shelled fruit of some plants having an indehiscent seed.
- While a wide variety of dried seeds and fruits are called nuts in English, only a certain number of them are considered by biologists to be true nuts.
- Nuts are an important source of nutrients for both humans and wildlife.
- Nuts are a composite of the seed and the fruit, where the fruit does not open to release the seed.
- Most seeds come from fruits, and the seeds are free of the fruit, unlike nuts like hazelnuts, hickories, chestnuts and acorns, which have a stony fruit wall and originate from a compound ovary.
- Culinary usage of the term is less restrictive, and some nuts as defined in food preparation, like pistachios and Brazil nuts, are not nuts in a biological sense.
- Everyday common usage of the term often refers to any hard walled, edible kernel, as a nut, and this journal follows that lead.
- A nut in cuisine is a much less restrictive category than a nut in botany, as the term is applied to many seeds that are not botanically true nuts. Any large, oily kernel found within a shell and used in food may be regarded as a nut.
- Because nuts generally have a high oil content, they are a highly prized food and energy source.
- A large number of seeds are edible by humans and used in cooking, eaten raw, sprouted, or roasted as a snack food, or pressed for oil that is used in cookery and cosmetics.
- Nuts (or seeds generally) are also a significant source of nutrition for wildlife. This is particularly true in temperate climates where animals such as jays and squirrels store acorns and other nuts during the autumn to keep them from starving during the late autumn, all of winter, and early spring.
- Nuts used for food, whether true nut or not, are among the most common food allergens.