Food is any material eaten to provide nutrition to the organisms. Food is generally of animal, plant or fungi origin, and has necessary nutrients, including proteins, carbohydrates, vitamins, or iron, that are required for the growth of an organism. The word ‘food’ is derived from the Greek word ‘gourmet’, which means good, and it derives its name from the Latin word ‘gavium’ meaning to attract. In its simplest form, food is a nutrient-rich mixture of water, fat, sugar, salt, and any other soluble matter that provide the necessary building blocks for growth and development of an organism.

Food can be grouped into four main categories, all of which together form the basic food groupings in modern diets; carbohydrates, protein, vegetables, fruits, and fibre. In modern diets, there are usually around 70 different types of food that we consume on a daily basis. The classification into these four groups is largely based on how the foods are prepared, eaten, and the amounts of those nutrients present in each food.

The cereal food groupings include such familiar foods as: oats, barley, millet, sorghum, faro, millet, triticale, kamut, emmer wheat, spelt, kourdi, spelt, wheat, corn, triticale, flax, buckwheat, chia, molybdenum, jicama, quinoa, millet, seitan, triticale, papaya, mango, guar gum, ginger, alfalfa sprouts, legumes, green leaves, herbs, and spices. Herbs and spices are included in foods as spices and flavouring agents, because they provide food colour and distinctive aroma. Examples of herbs used commonly in Indian and Sri Lankan cuisine are cumin, cardamom, basil, cilantro, mint, ginger, parsley, thyme, oregano, Rosemary, cloves, ginger, garlic, dal, and coconut oil. Some other examples of nutrients found in foods are: calcium, iron, zinc, phosphorus, manganese, magnesium, sodium, and potassium. Fruits and vegetables are also grouped according to their nutritional value.