Get me out of here!
Reef or Square Knot
Bowline
Double or Clove Hitch
Originally named for knots used to tie down sails during 'reefing'. Easy to tie, but  has unearned reputation for strength and reliability.
Another knot from the Age of Sail, the bowline connected the front edge of  square sail to the ship's bow for close-hauled sailing, earning its reputation for strength. It is known as the sheet bend when used to join two pieces of rope of the same or different thickness.
Created by two half-hitches, this knot is used to tie things that need to be adjusted in length or easily released, for example fenders and dinghy painters.
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