Like sheets, a pillowcase provides a lighter layer for a heavier part of your bedding. The advantage to this lighter layer, which can be easily removed, is that it is easier to clean or replace. This way you can clean the layer around your pillow that you touch without having to wash the entire pillow (at least not as often). It also makes it easier to change the aesthetics of your pillows -- the way they look and feel. In some situations a pillowcase can provide additional health benefits. For example, some pillowcases have a very tight weave to reduce the number of dust mites, which are allergens for some people.
- fabric material: cotton, silk, polyester, linen, etc.
- color or print
- touch: smoothness, etc.
- size (pillows come in different sizes, will your pillowcase fit?)
- ease of cleaning (can it go in the automatic washing machine?)