Kfb is an increase that uses 1 stitch to make 2 sts. A kfb looks like a knit stitch and a little purl stitch off of it. We use this increase in the Flax pullover, an adorable free pattern that is part of The Simple Collection.
::: How to work kfb (knit front and back) :::
Step 1: knit into the next st without taking it off the left hand needle. You now have a loop on both the right and left needle.
Step 2: knit into the same stitch again through the back loop and take it off the left hand needle.