Line to line knots are used to tie one fishing line to another. Using the correct type of know will ensure a secure connection that won’t come undone or break. One of the most tried and true line to line knots used by anglers is the Blood Knot. Many fisherman consider the Double Uni Knot just as reliable as the Blood Knot but much easier to tie. However, test suggests that the J knot is best all around line to line knot.
For joining fly line to leader, the Nail Knot is one of the best. But when joining fly line to backing or lines of different materials such as braid to mono filament, there’s nothing more effective than the Albright Knot.