String

String is an item that was added to the game in Indev. String is primarily received by killing Spiders or Cave Spiders, which drop 0 - 2 strings on death, but can also be obtained by destroying Cobwebs and Tripwires, which drop only one piece. String has an approximately 53% chance of spawning in a Dungeon chest, where it will appear in stacks of 1 - 4 units. This is not a practical way to find String though, since killing spiders can be used to get string more quickly and in larger amounts. In Abandoned Mine Shafts and libraries in Strongholds there are Cobwebs which can be cut with a sword or shears to get string. Tripwire (along with Tripwire Hooks), generate in Jungle Temples, which can be punched for collection, but also sheared and not activate any redstone.

Crafting
String is a vital component to two recipes, the Bow and the Fishing Rod. String can also be used to make Wool, but this is rather wasteful as Wool can be obtained from Sheep. It is more economical that you save your string for making more Fishing Rods or more Bows that can be used to make Dispensers.

String, as of 12w22a, can be placed on the ground as a Tripwire. Hooking them up to Tripwire Hooks will allow Redstone current to be activated by mining or walking over the string. It is difficult to see the string, making it useful in traps.

String can also be obtained by cutting Cobwebs and Tripwires. Cobwebs are mostly found in abandoned mineshafts, but also in stronghold libraries. Tripwires are found naturally currently only in jungle temples.

Trivia

 * For a period in Indev, Mob drops were random. The Mobs at the time had a chance of dropping String, Gunpowder, Feathers, or Flint and Steel. This can be seen with a Sheep dropping String. This was changed in an Indev update on February 19, 2010. Spiders were made to drop only String, and other mobs dropped only their respective items.
 * Prior to Beta 1.6.6, nine pieces of string, one in each square of the large crafting grid, were needed to craft one block of wool.

Faden String/es Fil Fonál Draad Nić pt-br:String Нить 线