Angling is a method of fishing by means of an "angle" (fish hook). The hook is usually attached to a fishing line and the line is often attached to a fishing rod. Fishing rods are usually fitted with a fishing reel that functions as a mechanism for storing, retrieving and paying out the line. The hook itself can be dressed with lures or bait. A bite indicator such as a float is sometimes used.
Angling is a principal method of sport fishing, but commercial fisheries also use angling methods such as longlining or trolling. Catch and release fishing is increasingly practiced by recreational fishermen. In many parts of the world, size limits apply to certain species, meaning fish below and/or above a certain size must, by law, be released.
The species of fish pursued by anglers vary with geography. Among the many species of salt water fish that are caught for sport are swordfish, marlin, tuna, while in Europe cod and bass are popular targets. In North America the most popular fresh water sport species include bass, pike, walleye, muskellunge, yellow perch, trout, salmon, catfish, crappie, bluegill and sunfish. In Europe a large number of anglers fish for species such as carp, pike, tench, rudd, roach, European perch and barbel . Although some fish are sought for their value as food, others are pursued for their fighting abilities or for the difficulty of pursuit.
The use of the hook in angling is descended, historically, from what would today be called a "gorge." The word "gorge", in this context, comes from the French word meaning "throat." Gorges were used by ancient peoples to capture fish and animals like seal, walrus and birds. A gorge was a long, thin piece of bone or stone attached by its midpoint to a thin line. The gorge would be baited so that it would rest parallel to the lay of the line. When the game would swallow the bait, a tug on the line would cause the gorge to orient itself at right angles to the line, thereby sticking in the fish or animal's throat. gullet.
Which of the various techniques an angler may choose is dictated mainly by the target species and by its habitat. Angling can be separated into two main categories: using either artificial or natural baits.