Trim, Couching, Curves, Zigzag, Decorative, Elastics, Stacking, Trim, and of course Braid...just to name a few. What have you used it for?

Bernina foot 21 https://www.bernina.com/en-CA/Accesso...
and here https://weallsew.com/creating-custom-...

The quilt in the background is in my book Sew Very Easy Quilt Favorites and here is the video    • Flowers on the Half-Log Cabin