The effect of glass shape on the taste of wine has not been demonstrated by any scientific study and remains controversial. It is however believed by some that the shape of the glass is important, as it concentrates the flavour and aroma (or bouquet) to emphasize the varietal's characteristic.

One common belief is that the shape of the glass directs the wine itself into the best area of the mouth from the varietal. This is based on false ideas about the nature of taste buds on the tongue, such as the thoroughly discredited tongue map.
 

Generally, the opening of the glass is not wider than the widest part of the bowl.
 

Most wine glasses have stems, although "stemless" wine glasses are now available in a variety of sizes and shapes as well. These glasses are typically used more casually than their traditional counterparts, as they negate the benefits of using stemmed wine glasses.
 

Most common wine glasses can be divided into three types: red wine glasses, white wine glasses and champagne flutes. Wine tumblers (without stems) are also increasing in popularity.