Crystal is the preferred material for wine glasses because it is very clear and thin. The thickness of the glass will also affect the taste. Taste depends greatly upon where the wine touches the tongue, and thin glasses, combined with the shape, direct the wine to the appropriate area of the tongue for the best taste. Thicker glasses send the wine to the wrong part of the tongue, which throws off the taste. However, thinner wine glasses are easier to break, so you will need to balance durability with functionality to suit your specific needs. One final consideration is whether or not the glasses have a stem. Most wine lovers will tell you to go with a stemmed glass because it keeps your hands from warming the wine up; wine is meant to be served at cooler than body temperature. However, stemless glasses are a growing trend, and many people do not expect to hold the wine glass long enough to warm up the wine.