Fish are aquatic vertebrates that are typically cold blooded, covered with scales, and equipped with two sets of paired fins and several unpaired fins.

Fish are abundant in the sea and in freshwaters, with species being known from mountain streams (e.g., char and gudgeon) as well as in the deepest depths of the ocean (e.g., gulpers and anglerfish).

Fish account for more than half of the known vertebrates.

There are at least 24,600 known species of fish, of which over 23,000 are bony fish, with the remainder being about 850 sharks, rays, and chimeras and about 85 hagfishes and lampreys.

They range in size from the 16 m (51 ft) whale shark to a 8 mm (just over 1/4 of an inch) long stout infantfish.

They are of tremendous importance as food for people around the world, being either collected from the wild or being farmed in much the same way as cattle or chickens..

For more information about the topic Fish, read the full article at Wikipedia.org, or see the following related articles:

Fish migration — Many types of fish undertake migrations on a regular basis, on time scales ranging from daily to annual, and with distances ranging from a few meters ...  > read more

Marlin — The marlin is a large game fish. It has an elongated body, up to 2.5 m long, a spearlike snout, and a long rigid dorsal fin, which extends forwards ...  > read more

Deep sea fish — Deep sea fish is a term for fish that live below the photic zone of the ocean. Examples include the lanternfish, flashlight fish, cookie-cutter ...  > read more

Trout — Trout is the common name given to a number of species of freshwater fish belonging to the salmon family, Salmonidae. Trout are usually found in cool, ...  > read more

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