The Bowline is also known as the King of Knots as it is one of the most important maritime knots.
The Bowline makes a secure non slip loop in the end of a piece of rope. It has many uses such as fastening a mooring line to a ring or a post and attaching sheets to sails. It can easily be tied or untied when not under pressure, but becomes more stable when under pressure.
To tie the knot form a small loop leaving enough rope for the desired loop size, ensuring the working line is on the bottom.
Pass the end of the rope through the loop, continue round the working line and back through the small loop.
You will often hear the rabbit method of learning: The end of the line is the rabbit and the standing line is the tree trunk. Once the loop is made this is the rabbit's hole, the rabbit comes up the hole, around the tree trunk and then back down the hole.
Video demonstration bowline