These listings show a few common materials: 100% PEVA (polyethylene vinyl acetate), 100% cotton, and 100% polyester (voile).
Most listings show a standard 72-inch height with widths around 70 or 72 inches (examples include 72" H x 70" W and 72" H x 72" W).
They typically use a buttonhole-style top (buttonholes along the top edge) and are hung on a rod with curtain hooks or rings.
A buttonhole top is the common hanging style; one listing specifically notes 12 buttonholes along the top for hanging.
Sheer and translucent curtains let light into the shower and provide a translucent look but offer limited privacy; one listing suggests using an opaque liner if you want more coverage or a solid appearance.