Redstone torches are the basic of standard logic in Minecraft computing. It powers directly blocks directly above it, and on it's four sides. Redstone repeaters, other torches, and Redstone wire can be powered from these blocks. The most useful feature of the redstone torch, is that when the block it is standing on is powered, it turns off. Likewise, when it is not powered, it turns on. Because more than one wire can power a single block, a single repeater can function as either an NOT gate or an OR gate with up to two to four inputs. However, changing state like this introduces a 0.1 second delay, or one tick. A last (and less useful) property is that Redstone torches give off a light level of 9 when powered.