Sweet wines are delicious with dessert and cheese or, less commonly, as an aperitif. Matching helps - e.g. red dessert wines are better with chocolate - but there’s leeway - e.g. a Sauternes with blue cheese is amazing, but most sweeties are. Various techniques allow ‘stickies’ to retain sweetness while fermenting some sugar into alcohol. Late harvest wine boosts the starting sugar by over-ripening grapes - and/or getting them get fully raisined by botrytis (‘noble rot’). ‘Straw wine’/Vin Santo concentrates sugars by drying on mats, Icewine does it by removing water (ice crystals). Stopping fermentation mid-way also retains sweetness: Port and Sherry stop ferment using alcohol fortification, while Moscato d’Asti uses freezing (cold stabilisation).