A fishing line is a cord used or made for angling. Important parameters of a fishing line are its length, material, and weight (thicker lines are more visible to fish). Factors that may determine what line an angler chooses for a given fishing environment include breaking strength, knot strength, UV resistance, castability, limpness, stretch, abrasion resistance, and visibility. Most modern lines are made from nylon or silk.
Fish are caught with a fishing line by encouraging a fish to bite on a fish hook. A fish hook will pierce the mouthparts of a fish and is normally barbed to make escape less likely. Another method is to use a gorge, which is buried in the bait such that it would be swallowed end first. The tightening of the line would fix it cross-wise in the quarry's stomach or gullet and so the capture would be assured.
Fishing with a hook and line is called angling. In addition to the use of the hook and line used to catch a fish, a heavy fish may be landed by using a landing net or a hooked pole called a gaff.
Trolling is a technique in which a fishing lure on a line is drawn through the water. Trolling from a moving boat is a technique of big-game fishing and is used to catch large open-water species such as tuna and marlin. Trolling is also a freshwater angling technique often used to catch salmon, northern pike, muskellunge and walleye. This technique allows anglers to cover a large body of water in a short time.
Long-line fishing, also known as a trot line is a commercial fishing technique that uses many baited hooks hanging from a single line.
Snagging is a technique where the object is to hook the fish in the body. Generally, a large treble hook with a heavy sinker is cast into a river containing a large amount of fish, such as a Salmon, and is quickly jerked and reeled in. Due to the often illegal nature of this method some practitioners have added methods to disguise the practice, such as adding bait or piercing the jerking motion.