Page 18 - Peter Randall "The Craft of the Knot.."

The Overhand Knot and the Multiple Overhand Knot structures are used
in many knots, and it is valuable to become familiar with their form. The
following illustration shows the shape of a Multiple Overhand Knot of
three turns in what is called its “belly-and-spine” form (the belly may
also be referred to as the bight).

When you tighten the Multiple Overhand Knot by pulling on both
ends, the belly wraps around the spine until it is barrel shaped, as shown
here.

THE BEST KNOT FOR THE JOB

When you open a drawer or box of tools, it is immediately obvious that
some of them are right and some of them are wrong for the job you have
in mind. When you have a job to do with rope, the knots you know will
serve you as your toolbox. Just as you would not have much use for a

toolbox with just one tool in it, you would not want to do different jobs
with rope or string with just one knot. You will want to learn a few
different types of knots and learn to use the right one for your
application.

The main categories of rope use are joining one rope to another,
making a loop, binding, and tying off to an object. Identifying the
function that the knot must serve is an important step in choosing one.
Some knots are like a multitool in that they can serve a variety of
functions, and some are very limited in what they do. A fixed loop will