wool - n - gather

Back post is usually used in conjunction with a type of stitch. For example BPdc or BPtr. To make a back post stitch you insert your hook from the back of your work and bring it around the post and back out the back of your work. The way to remember how to make this stitch is the hook ends up at the back of your work or that this stitch brings a stitch it is wrapped around to the back.