Infused oils contain a carrier oil (base oil) that has soaked up the goodness of the respective herb it is named from. These infused oils (depending on any contraindications) can be applied directly to the skin or added to your skincare recipes. Make sure you read about the herb for any cautions (ie St john's wort is phototoxic and can make you burn quicker when in the sun.)
Ointments and balms take these infusions further into a more usable thicker product, some with other added essential oils for additional benefits.