The pattern I am currently knitting uses these terms:
yfwd = yarn forward
yon = yarn over needle
yrn = yarn round needle
I don't understand what I am meant to do differently because I thought all these things meant the same!
But when it says: P5, yon, K1, yfwd, yrn, P4, then I am obviously meant to do something other than just a Yarn Over but what?
(The pattern is from Simply Knitting so I'm assuming these are UK knitting terms!)
It's the different transitions between purl and knit. So when you are going from purl to knit, you do yarn over needle to make an extra stitch. When you are going from knit to purl you bring the yarn forward first, then put it back over the needle and bring it forward again to loop it so you again get an extra stitch. They are fairly similar, it's where you have your yarn that counts. The main difference is with yarn round you have the yarn going all around the needle while yarn over only goes over the top of the needle. The yarn forward bit just gets your yarn in the right position (can be used in other stitches that don't involve increases, such as when you wrap a stitch in sock knitting).