Herbs are plants or parts of plants valued for their medicinal, aromatic, or savory qualities. They can be consumed, inhaled, or applied topically. Herbal products often contain various naturally occurring biochemicals from plants, many of which contribute to their medicinal benefits. These medicinally beneficial chemicals are referred to as "active ingredients" or "active principles," and their presence depends on several factors, including the plant species, the time and season of harvest, the type of soil, and the method of preparation.