The instructions to work a stitch “with yarn in front” or “with yarn in back” is commonly found in slipped stitch knitting patterns. In this video, knitting expert Jen Lucas explains these directions and shows how to work these instructions in a linen stitch pattern.
With yarn in front is often abbreviated as “wyif.” With yarn in back is often abbreviated as “wyib.” The abbreviations section of a knitting pattern will tell you for sure what the abbreviations are for these instructions. The front and back in these instructions refer to which way your fabric is currently facing – it is independent of the Right Side or Wrong Side of your knitted fabric.
When working a stitch “with yarn in front,” the yarn should be coming to the front of the work, which is the side facing up towards you. When working a stitch “with yarn in back,” the yarn should be going behind the work, or the side of the work that’s facing away from you.