Thyme is sold both fresh and dried. The fresh form is more flavourful, but also less convenient; storage life is rarely more than a week.
While summer-seasonal, fresh greenhouse thyme is often available year round. Fresh thyme is commonly sold in bunches of sprigs.
Dried thyme is widely used in Armenia (called Urc) in teas.
Depending on how it is used in a dish, the whole sprig may be used (e.g. in a bouquet garni), or the leaves removed and the stems discarded.
Usually when a recipe specifies ‘bunch’ or ‘sprig’, it means the whole form; when it specifies spoons it means the leaves.
It is perfectly acceptable to substitute dried for whole thyme.