Minecraft/String

Once placed, string is almost invisible, good for placing under carpets to make them appear to float.

Use
Apart from its value in crafting, string has one functional use: placing string in between tripwire hooks connects them, and steping on the string (but not the hook), breaking the string (but not the hook) or allowing an item to drop on the string causes both tripwire hooks to emit a redstone signal of 15, until no more preassure is applied (or for 0.2 seconds if you broke the string). This is good for making booby traps. A tripwire may not be more than fifty blocks long. Remember to hide the tripwire hooks though, they stand out as clearly as blue in a red background in almost every case. Simply put the hooks in a one block deep hole in the walls. See also: making traps.