A figure N knot is similar to a figure 8 knot, but it adds a number of additional twists. This often makes the knot easier to untie.
A figure 9 is a common figure N variant with just one additional half twist beyond a figure 8. A simple overhand is just a figure 8 with one less half twist. See below for (single strand, undressed) illustrations.
A figure 10 would be a figure 8 with a full additional twist.
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