There are 4 basic forms of herbal preparation; Infusion, Decoction, Tincture, Salve/Ointment. These preparations are used for applying or using herbal mixtures in different ways. Some herbs you want to ingest for them to work internally for digestion or to interact with any number out internal systems that need support. Some are for external uses for problems on the skin, like rashes, bruises or injuries.