the figure 8 knot (ABOK # 570, p 95.) can replace everything. well maybe not but lets see how many knots we can replace with a figure 8 knot

the easy knots a figure 8 knot can replace really well are:
overhand knot
tying a loop in the end of a rope
the truckers hitch is just the alteration of a figure 8 knot
Boline if you have both hands

Why use a figure 8 knot instead.
It doesn't bind up as bad after being under load is the main reason.
The second reason is partially nigated by hightech ropes, it maintains the strength of the rope better.
The third reason is it holds better with very slippery ropes like fishing line, UHMWPE Ultra High molecular weight Polyethylene rope, and dacron toe ropes.

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