Arbor Knot
In fly-fishing the Arbor Knot is used to secure the backing to the spool. It works with braided backing as well as mono and gelspun.
Notes
All knots should be lubricated before tightening. The idea is to reduce friction and heat generated as the fishing line tightens against itself. If a knot chaifs as it tightens it may significantly reduce the working strength of the line.