Raw Fish

Raw Fish is a food item obtained by fishing with a fishing rod in any source of water. Fish do not appear in the game as a mob and are only seen as an item when caught. Fishing is a reliable, fast source of food, as the player does not have to wait for pigs, cows, or chickens to spawn or for planted crops to grow. However, string is required to craft a fishing rod and early on in the game it may be difficult to acquire. It can be obtained without a fight from cobwebs, found in abandoned mine shafts and strongholds, and can be mined with a diamond sword and shears at the same speed. Or from tripwires in jungle temples. Later in the game, if you are sufficiently armed, string can be acquired from spiders.

Like porkchop, beef, or chicken, raw fish can be placed in a furnace to produce cooked fish, for 1.5 additional hunger points (raw fish heals and Cooked Fish heals ).

Being obtainable from any source of water, both Raw and Cooked Fish are considered a renewable resource.

As of Snapshot 13w36a, different kinds of fish exist.

Advantages

 * A Raw Fish heals 1 hunger point. If you are really in need of food, it is very effective, as it is easy to gather.
 * This is especially worthy to note as you may lack a constant food source in a new survival game (a fishing rod is arguably easy to acquire).
 * Gathering fish can be initially faster than waiting for wheat to grow or finding animals to kill.
 * Since fish can be caught by any body of water, you can use a bucket of water to be able to catch fish anywhere.
 * Currently raw fish is the only way to tame an ocelot into a cat, which provide a safe zone from creepers around it as it follows you.
 * Farmer villagers sometimes require cooked fish as a trade. A stockpile of fish can help keep trading with farmers for longer, allowing more trades for wheat, raw chicken and wool.

Disadvantages

 * A fishing rod requires string to make, which can be difficult to obtain early on. By the time it is easy to find, you tend to have other food sources already set up.
 * You must be present the whole time you are fishing, which can be tedious.
 * Once a wheat farm is fully established, it produces wheat far faster than you can obtain fish.
 * Fish require cooking for their full effect.

Trivia

 * In the Halloween Update, Notch said he would add fish as a sea creature; however, he had limited time, and was thus only able to add them as an item.