Page 177 - Bob Holtzman "The Field Guide to Knots How to Identify, Tie, and Untie Over 80 Essential Knots for Outdoor Pursuits"

9. Figure 8 Knot

Also known as: Figure of 8 Knot, Flemish Knot

One of the most common and most useful stopper knots, the Figure 8 is
simple to tie and remember. It is frequently used to prevent lines from
running through small openings, and though it is not much bigger than an
Overhand Knot, it is easily untied. It is the basis for a whole family of
related knots.

Uses: stopper, sailboat main and jib sheets, fender pennants, tarp guylines
Pros: quick and easy to tie and untie; provides a good size handhold at a rope’s end

Cons: will not stop a hole larger than an Overhand Knot

Instructions

1. Make an overhand crossing turn, then pass the working end back under the standing part.

173