A quarter inch foot is a type of foot that you can buy for your sewing machine to help guide you to stitch an accurate ¼” seam. Some newer “quilter edition” sewing machines come with this foot. You can purchase this foot from a sewing machine shop or online.
On this quarter inch foot, the needle is exactly 1/4 inch from the edge of the foot. The foot also has notches that are 1/4 inch apart.