All wine glasses follow the same tulip-shaped design and have three essential components: the base, which keeps the glass upright; the stem, which allows a person to hold the glass without transferring his or her body heat to the wine; and a body conducive to maximum flavor and aroma for that particular type of wine. Experts recommend that glasses be made of crystal or other similar thin glass because thick glass is thought to influence the taste of the wine. They are all designed in a way that directs the wine to the parts of the mouth where its flavor will be most appreciated.
There are many types of wine glasses, but in general, only four are needed. Glasses for red wine are taller and wider so that the complexities of the wine can be better appreciated. People should have at least two types for their collection.
The first is a Bordeaux glass, which is designed for rich, full bodied red wines such as cabernets and merlots. The wide bowl allows the wine to breathe and brings out the rich aromas. Because the glass is tall, the wine proceeds directly to the back of the mouth allowing for maximum flavor. It's also a good idea to have a burgundy glass to use for other full bodied wines such as a pinot noir. Larger than the Bordeaux glass, the large bowl of the burgundy glass allows the wine to dispense to the tip of the tongue, where it's easier to taste the sweetness of the wine.
White wine glasses are smaller to help keep the wine cool. For a young crisp white wine, people will need a glass with an opening that's slightly larger than the body of the glass itself. This will allow the wine to dispense at the tip and sides of the tongue to better enjoy the wine's sweetness. A glass for more mature white wines is also recommended. This is a taller, straighter glass and will allow the wine to dispense to the rear and sides of the tongue to better taste the bolder flavor.
There are other glasses that a connoisseur might enjoy having in his collection. Champagne flutes are tall and thin, which will allow the bubbles to build up properly. Sweet wines, such as dessert wines, require smaller glasses that dispense the wine to the back of the mouth so the sweetness doesn't envelope the whole tongue and overwhelm by its flavor. Rose glasses are similar to those used for white wine in that they are smaller, though their bodies are wider to allow aromas to better develop.
Unless one is truly a wine connoisseur who understands and recognizes the complexities of all the different wines, there's no reason to have a different glass for each different wine. Most wine lovers use the use of four types of glasses, but individuals could probably get away with having one glass for each color of wine. The important thing is to use the glasses that provide the most enjoyment.