Why do wine glasses have stems?

With the growing interest in stemless wine glasses lately, you might wonder if stems are needed at all! If you are reading this, I'd guess that is the case. The stem on a wine glass serves two purposes.

1. It is a design element that allows the glass makers and designers to add style, complexity and visual interest to the glass.
2. Beyond being a design element, the stem allows you, the glass user, to keep your hands off the bowl of the glass. When looking at the wine, a stem grasp allows you to see the wine without any visual impairments from your hands. Also, swirling is easier when holding the stem. However, the single most important reason to have a stem on a wine glass is temperature control. When the glass is cupped in your hand heat transfers from your hand to the glass warming the wine quicker than room temperature air would on its own. While red wines are served at warmer temps than white wines, they shouldn't be allowed to get too warm as it can affect the aroma and flavor (and therefore your enjoyment) of the wine.

Maybe the question shouldn't be 'why are there stems on wine glasses?', maybe it should be, 'why are there stemless wine glasses?'