Materials
Flannel sheets, on the other hand, are great for keeping warm during the colder months. Flannel sheets are made of cotton or wool and are known for their softness and insulation. When choosing flannel sheets, pay attention to the weight of the fabric, as heavier weights are generally warmer and more durable. Choose flannel sheets that weigh 5 ounces or more for a comfortable and long-lasting option.

In terms of fitted sheets vs. flat sheets there are distinctions in design, functionality, style, and the experience they offer.

Bed sheets come in two main varieties: flat and fitted. A flat sheet is simply a rectangular sheet of cloth, while a fitted sheet has four corners, and sometimes two or four sides, fitted with elastic, to be used only as a bottom sheet. The fitted sheet may also be secured using a drawstring instead of elastic. The purpose of a fitted bottom sheet is to keep it from slipping off the mattress while the bed is in use. A particular way of folding and tucking while making the bed, known as hospital corners, is sometimes used when the bottom sheet is flat rather than fitted.
Green sheets, on the other hand, can bring a calming and natural vibe to a bedroom, while purple sheets can add a touch of luxury and sophistication.