What is a "rod pocket curtain"?

A rod pocket curtain is a type of window treatment that features a sewn-in pocket along the top of the curtain panel. The pocket is designed to fit over a curtain rod or other types of hardware, and allows the curtain to be easily hung. Rod pocket curtains can be made from a variety of fabrics, including cotton, linen, or silk, and come in a range of styles and patterns. They are typically lightweight and airy, and can be easily adjusted to control the amount of light entering a room.