Also known as the Fish-N-Fool.
The Fish-N-Fool Knot is a knot invented by an Idahoan angler that sits atop the knot strength chart. It has great knot strength efficiency across all line types, and bested nearly every other knot in a series of head to head competitions for measuring knot strength and efficiency. Like many of the strongest knots, it employs a double line tying technique, which allows it to achieve a high level of breaking efficiency.
Here are the knot strength efficiency numbers for the Fish N Fool Knot as tested across the three major line types.
See the Fishing Knot Strength Chart for more data and details on the testing methodology.