Interfacing and stabilizers are typically used between two layers of fabric in apparel and accessories. Stabilizers provide structure for projects like tote bags and crafts, whereas interfacing is generally used to provide more body in apparel projects like collars and facings. The heavier the weight, the more body or structure it provides.
Interfacing and stabilizers are available in sew-on and fusible varieties. Hair canvas interfacing is a little stronger and contains a small percentage of horsehair. It’s used in heavy-duty tailoring projects, like coats and jackets. In-sewn fleece interfacing is heat resistant, making it good to use for things like potholders and table pads. Web interfacing can be using clothing and DIY projects. It is popular for embroidery and craft stitching because it can be used as a stabilizer for stitching.