The main difference between Prosecco Brut and Extra Dry lies in the level of sweetness of the wine. Prosecco Brut is generally considered drier than Extra Dry. The classification "Brut" indicates that the wine has a low residual sugar content, typically below 12 grams per liter. As a result, Prosecco Brut has a dry and crisp note, with a balance between acidity and fruity aromas.