Fishing line types

Line is the only thing between you and the fish, and the three materials it comes in behave differently on every axis that matters: stretch, visibility, diameter, and whether it sinks. None of the three wins outright. Each owns a set of jobs.

Monofilament

Mono is a single extruded strand of nylon. It stretches up to a quarter of its length, floats, ties easily, and costs the least. The stretch is a built-in shock absorber: it cushions hard strikes, forgives a heavy hand, and keeps treble hooks pinned. The same stretch mutes sensitivity and slows hooksets at range. Mono is also the thickest of the three per unit of strength, and it weakens with UV exposure, so it wants replacing every season or two.

Fluorocarbon

Fluorocarbon looks like mono, but the polymer bends light at nearly the same angle water does, which makes it the closest thing to invisible below the surface. It sinks, stretches less than mono, and resists abrasion well, so it earns its keep around rock and for line-shy fish in clear water. The costs: stiffer, springier off a spinning spool, less forgiving in knots, more expensive. Many anglers use it only as a leader in front of another line, which buys the invisibility without spooling a whole reel of it.

Braid

Braid is woven from polyethylene fibers, and its numbers read like a misprint: 30 lb braid can run the diameter of 8 lb mono. Near-zero stretch means every tick of the bottom reaches your hand and a hookset arrives instantly even with a long line out. The thin diameter casts farther and slices through grass. In exchange, braid is opaque and visible, so it usually fishes behind a mono or fluoro leader, and the missing stretch pushes the shock-absorbing job onto the rod and the drag. It also demands its own knots; the slick fibers slip knots that mono holds.

Choosing

• One line, general fishing: mono. Forgiving, cheap, good enough at almost everything.
• Clear water, pressured fish, bottom contact: fluorocarbon, full spool or as a leader.
• Distance, grass, feel, deep water: braid with a leader tied in front.

One vocabulary collision to keep straight: in fly fishing, leader and tippet name a tapered, standardized system of their own, related to a braid-plus-leader rig in function only. The materials above still apply there. The sizing does not.