Fisherman knots

Fisherman’s knot, also known as English knot, consists of two overhand knots each one tied around the standing part of the other one. Though it is mainly used as a bend to join two lines, it can be easily used to connect the ends of a single length of rope to form a loop. The beauty of the knot lies in its symmetry.

https://www.netknots.com/rope_knots/fishermans-knot