Chamomile, peppermint, and ginger can be dried, processed, and steeped in hot water to produce a tasty hot beverage, but they are not teas. This distinction of name is important because anything called a "tisane" does not come from camellia sinensis (the tea plant).
Our tea master, Doug, describes the difference like this:
You have two very different animals in a dog and a cat. Both might live inside your house, and both might be mammals, but they're totally different creatures. Likewise, teas and tisanes are both dried plants that brew in hot water, but that's about all they have in common. They're totally different animals.
Most commonly, tisanes are consumed for medicinal purpose. Over time, witch doctors turned into apothecaries, and gradually apothecaries turned into doctors. The funny thing is that we're now coming full circle as modern medicine is turning to holistic methods of medicine like tisanes to treat certain symptoms.
Mostly these are caffeine free but this is not always true. People frequently assume this, but Mate tea, for example is not.