Brut - The most common form of non-vintage (NV) champagne, is a blend of wine from multiple vintages. Producers could blend anything up to 40% of vintage wine, but typically 10-15%. Around 12-15 grams of sugar is added to formulate the blend. Vintage brut is produced similarly, however it goes through an extended ageing process.
Brut Nature - Champagne that contains very little or no sugar, typically 0-3 grams per litre
Extra-brut - Champagne that contains little sugar, typically anything up to 6 grams per litre
Extra Dry / Extra Sec - This type of Champagne contains a little more sugar than Brut, typically 12-17 grams per litre.
Blanc de blancs - is a white Champagne created entirely from Chardonnay for example Ruinart