Fusible Web is a glue substance that is adhered with heat to fabric. It has several brand names and each is preferred by someone. The ones I recall and have used are Wonder Under; Heat n Bond Lite, Heat n Bond Ultra; Steam a Seam; Steam a Seam Lite; Misty Fuse. Stitch Witchery --- most of these have paper backings. For banners without sewing I prefer the Heat n Bond Ultra (red label) as if used as directed it truly does work. Whichever fusible web one chooses, prewash all fabrics without any fabric softner used in the washer or the dryer. The prewashing helps insure that the glue of the fusible webbing attaches to the fibers of the fabric. Another trick is to just barely touch it in spots until the final heat set is done. Too hot, too long will mean that the heat activated glue may not adhere to the fabrics.The glue will melt towards the heat source not the bottom fabric.