A vegetable is the edible portion of a plant. Vegetables are usually grouped according to the portion of the plant that is eaten such as leaves (lettuce), stem (celery), roots (carrot), tubers (potato), bulbs (onion) and flowers (broccoli).A fruit is the mature ovary of a plant. So a tomato is botanically a fruit but is commonly considered a vegetable. According to this definition squash, pepper and eggplants are also fruits. Then there are seeds such as peas which are also considered vegetables.Vegetable, the edible product of a herbaceous plant-that is, a plant with a soft stem, as distinguished from the edible nuts and fruits produced by plants with woody stems such as shrubs and trees. 

Fruit, mature ovary in flowering plants, together with all inseparably connected parts of the flower. In strict botanical usage, the meaning may be restricted to the ovary alone. Commonly the term fruit is often restricted to succulent, edible fruits of woody plants, to melons, and to such small fruits as strawberries and blueberries. In nature, fruit is normally produced only after fertilization of ovules has taken place, but in many plants, largely cultivated varieties such as seedless citrus fruits, bananas, and cucumbers, fruit matures without fertilization, a process known as parthenocarpy. In either case, the maturation of the ovary results in the withering of stigmas and anthers and enlargement of the ovary or ovaries.