Pinot Blanc is a white grape mutation of Pinot Grigio, which is itself a mutation of Pinot Noir. It has more roundness of flavour and less acidity than these relatives, though, which can give it a slight sweetness (depending on where and how it is grown). It is mostly drunk as a young wine, when the weak acidity is still noticeable, but when produced in low enough yields it can be barrel aged. While often dry or semi-dry, Pinot Blanc is also used in sweet and sparkling wines.
The character of the grape depends on where it is grown. It originates in Alsace, where it is a staple white. Here it is often aged in oak barrels to give its wines notes of apples and spices, with a creamy texture. In Austria, as Weissburgunder (“White Burgundy”), it has a growing influence, capable of easy ripening and barrel ageing. The grapes here are often left on the vine until shrivelled and with a high sugar concentration in order to make the sweet Trockenbeerenauslese (or TBA). Italy has the most vines planted, however, where it is known as Pinot Bianco and used in a wide variety of ways, from sparkling to refreshing, aged wine. Its popularity in Italy may be due in part to it being mistaken for Chardonnay in the northeast of the country during the 1980s, when Chardonnay was the height of fashion.
Despite these local variations, Pinot Blanc has a few characteristics that are constant. It has light flavours and a medium to full body, and is similar to Chardonnay in these respects. You can expect flavours of apricot, melon and pears, as well as occasional notes of minerals and smoke.