Herb refers to a leaf of a plant.

Dried herbs against fresh:
The water content from dried herbs is gone, oil are preserved (concentrated),
they amalgamate and infuse into the food more readily and have more robust flavour

Storing fresh herbs
In the fridge: in water (changed often), wrapped in a damp J-cloth,
In the freezer: chopped and frozen in ice-cube trays with a little water for soft leaves (basil, parsley, coriander…) or whole for bay leaves, thyme and rosemary