Beans: Beans are seeded pods of various legumes. They are among the oldest foods known to humanity, dating back at least 4,000 years. Legumes: Legumes are any of thousands of plant species that have seed pods that split along both sides when ripe. Some of the more common legumes are beans, lentils, peanuts, peas and soybeans. The high-protein legumes contain some Vitamin B, carbohydrates, fats and minerals.