I was asked what the knot is at the bottom of the 2nd Class and 1st Class scout rank badges that reminds scouts to do a good turn daily, and how to tie it.

It is an overhand knot in a bight and it's pretty simple to tie but has few uses. Now you can impress all your scouting friends on your next campout by learning to tie it.

On the actual embroidered badges, it's difficult to make out and there are different versions of the knot, but you can see the full size official image by clicking this thumbnail -

See the Guide to Tieing this Knot.