Hi, JudyJo! :D
I just call it a hopping foot. It is called an open toe free motion or darning foot. It has a spring on it to hold the fabric down when the needle comes out and is used in place of a regular foot on the sewing machine so one can sew in any direction.
As for the family knowing what to get...... I either get it myself or they know any cotton fabric for quilting will do. Sometimes I make a detailed list and where to get it. They are all clueless when it comes to quilting lingo. That way I get what I want. :twisted: