Fishing Line Explained

Fishing line is the flexible, high-strength cord between your reel and your hook. Wikipedia lists the properties that matter: breaking strength, knot strength, UV resistance, castability, limpness, stretch, memory, abrasion resistance and visibility. This guide explains the main line types, how a modern setup is built from several sections, and a few practical points from state agencies and anglers. For choosing a line for a given fish, see how to choose fishing line.

The three main line types (Wikipedia)

Monofilament

A single strand, usually nylon, and the most common type. Anglers like it for its buoyancy and stretch: the stretch cushions the hookset and the fight with strong fish, though Wikipedia notes this damping can become a disadvantage at very long distances.

Fluorocarbon

Made of the fluoropolymer PVDF. Its refractive index is close to water’s, which makes it less visible to fish. It is denser than monofilament and sinks, so anglers use it when they want a bait to stay nearer the bottom without heavy sinkers. Wikipedia notes clear, low-visibility materials like fluorocarbon are common for leaders.

Braided and fused lines (“superlines”)

Braided, thermally fused and chemically fused lines are known for small diameter, little stretch and great strength relative to nylon monofilament. New York DEC gives an example of the diameter difference: 80-pound braid has about the diameter of 17-pound monofilament.

How a line is built

Most modern setups use at least two sections joined with a knot (Wikipedia):

• Backing: the rearmost line on the spool. It pads the spool so the mainline doesn’t slip, raises the effective spool diameter, and is a reserve if a big fish takes all the mainline. Fly reels use braided Dacron or gel-spun backing.
• Mainline: the main section, which takes most of the load.
• Leader: the front section tied to the hook or lure, often clear fluorocarbon or wire. A leader with a lower breaking strength than the mainline also acts like a fuse: it breaks first and protects the rest of your tackle.
• Tippet: in fly fishing, a secondary leader for small flies, sized by “X” from about 0X (thickest) to 8X (thinnest).

Our line and leader strength tool helps balance the sections.

Wire leaders

Wire leaders keep toothy fish from cutting the line and resist abrasion (Wikipedia). Single-strand wire is stiff but very strong; multi-strand is more flexible but more prone to damage; titanium-nickel leaders are flexible, stretch without permanent damage and resist corrosion. MDC recommends a steel leader for muskie so the fish can’t cut the line with its teeth.

Fly lines

A braided or monofilament core inside a thick waterproof plastic coating; floating lines have tiny air bubbles in the coating. Fly lines are attached to backing behind and a monofilament or fluorocarbon leader in front (Wikipedia).

Knots on braid

Slick braid holds some knots worse than monofilament. An Outdoor Life frog-fishing guide notes that knots such as the clinch, which work well with monofilament, tend to slip on braid, and uses a Palomar instead. Our knot picker helps choose a knot for your line.

Discarded line

Wikipedia notes discarded monofilament can take up to 600 years to break down, and abandoned line can entangle fish, birds, turtles and marine mammals. Take old line home, or put it in a line-recycling bin where one is provided.

Sources

• Wikipedia, Fishing line. Read 28 October 2026.
• New York State DEC, Muskie 101. Read 28 October 2026.
• Missouri Department of Conservation, Muskellunge: tips for fishing. Read 28 October 2026.
• Outdoor Life, How to fish frog lures to catch giant bass. Read 28 October 2026.

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Recommended Gear on Amazon

• Braided fishing line - browse current options and reviews on Amazon.
• Fluorocarbon line - browse current options and reviews on Amazon.
• Monofilament line - browse current options and reviews on Amazon.

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