What is a Duvet Cover?
Ok, so the first step in understanding what a duvet cover is, is understanding what a duvet is. This is complicated because different countries call a duvet different things. In the United States a duvet is often called a comforter. The duvet cover is the piece of bedding that goes around the duvet.
So what exactly is a duvet? A duvet is a soft flat bag, filled with a bedding material. This material is often down, but can also be synthetics, wool or silk. You can think of a duvet as similar to a bed-sized pillow. Rather than sleeping on top of it though, you sleep under it like a blanket. Again, it's a big bag, filled with bedding material you use to keep you warm while in bed.
Unlike other types of bedding a duvet is a single cover which is often used alone to provide all the warmth one needs when sleeping. Because it is a single cover, making the bed is easier than having many different blankets and sheets to sleep under.
So if you think of a duvet as a pillow, a duvet cover is like a pillow case. It is a thin bag - often cotton or silk - which is placed around the duvet. A duvet cover serves a number of purposes. Primarily it keeps the duvet clean. A duvet can be difficult to wash. Down is especially difficult to wash and often requires dry cleaning. A duvet cover protects the duvet from dirt, oils and sweat. Instead of having to dry clean the duvet, placing the duvet cover into the wash is all that is needed to clean the bedding.
A duvet cover also helps protect sleepers who may have allergies. Certain duvet filling, specifically down, can cause allergic reactions in some people. Special anti-allergy duvet covers exist to help mitigate this. They allow allergy sufferers to use down and other types of duvet fill, without suffering from an allergic reaction.
Another benefit of a duvet cover is the ability to cheaply change the style of the bedding. Your bed is the centerpiece of your bedroom. You want the bedding to match and reflect the character of the bedroom. Changing the look of your bedding can often mean purchasing a whole need comforter set, new sheets, new blankets, etc. With a duvet cover you can keep your existing duvet, but change the look of it by simply getting a new duvet cover. Changing the color and style of your bed is easy with a duvet cover.
Think of the reasons for using a pillow case. A duvet cover is used for many of the same reasons. With a duvet cover chores like making the bed and washing the bedding will be made easier. Your duvet will also last longer when it is protected by a duvet cover.