Herbs can be used in many ways including seasoning food, for medical purposes, fragrance, religious practices and magic.
Which part of an herb is used depends in part on what it's being used for. Cooks generally use the leaves but when an herb is used for healing, any portion of an herb might be used. Herbs harvested for medical purposes often come from shrubs or woody plants while herbs used in cooking come from woodless plants. Cooking herbs are used carefully because it only takes a little of one to generate a lot of flavor. Spices are often made from herbs by drying the seeds, berries, bark, root, fruit or other parts of the plant.