Redstone is probably the most complicated mechanic in the game, and often confuses players who aren’t already familiar with circuitry or engineering. Allow me to explain to you what each piece of redstone equipment does.
Redstone dust: act as wiring to transmit redstone signals. It can be placed only on top of blocks, but will automatically link together upon contact with each other. You can even run it up a 1-block slope.
Power Sources
Solid, basic blocks (such as dirt and stone): Redstone signals can pass through single blocks and affect a device on the other side. This can be used to save space and can even be used as a way to toggle a contraption on or off.
Redstone torches: emits a constant redstone signal which will be carried on by any dust that’s next to it/on top of it. All power sources emit a 15-block strong signal before losing its energy and dying out on the 16th block (with the exception of weighted pressure plates and daylight sensors). Be aware, if a signal is running towards a redstone torch, said torch will be turned off.
Lever: emits a constant redstone signal just like the torch, but is more practical considering that you can turn it off or on at your decision.
Wood/Stone Buttons: Emits a brief redstone signal after it’s pressed. The difference between Wood and Stone Buttons is that Wood buttons give off a slightly longer-lasting signal than the Stone one, but this is so miniscule that it probably doesn’t matter. Also, you can activate a wood button by shooting a projectile at it (such as an arrow), but you can’t do so with a stone button.
Redstone block: basically another redstone torch, except it’s impossible to turn off. It can also be moved around without breaking with the help of pistons.
Daylight Sensor: emits a redstone signal, its strength depends on the amount of daylight it receives, maxing out at the regular 15 blocks. It can be turned into “night mode,” which outputs a redstone signal based on how dark it is.
Wood/Stone Pressure Plates: emits a redstone signal when any amount of weight is applied to it. Similar to the buttons, stone pressure plates are slightly more stubborn, as wood plates can be activated by dropped items, but stone ones cannot.
Weighted Pressure Plates: can only be crafted using iron or gold, and its signal output depends on how much weight is on it. The only difference between the two is that the Iron one needs less weight to produce power while Gold plates need more weight to produce the same amount.
Detector Rail: A special kind of track that emits a signal whenever it detects something on top of it (in this case, a minecart). It can also have a varying signal output. For example, a minecart with a full chest will cause it to emit a max-strength signal, but a minecarft with an empty chest won’t emit as powerful of one.
Observer: a block that will emit a redstone signal whenever it detects a change to the block/fluid it’s looking at. For example, breaking a block in front of an observer will cause it to emit a signal.
Target: can be used to power a signal when struck with a projectile such as a thrown trident. It also has the ability of redirecting already-powered signals, but only when the target itself is powered.
Devices
Powered Rail: A device that is used as an accelerator for minecarts, boosting its speed as long as it’s powered by a redstone signal. If it is not powered, then it acts as a brake and causes any minecarts that travel over it to grind to an immediate halt.
Piston/Sticky Piston: A device that, when powered, extends its arm one block out, pushing whatever block it’s attached to. However, only sticky pistons can pull blocks back. Pistons can push/pull a total of 12 blocks simultaneously.
Redstone lamp: A device that provides light when it receives a redstone signal, otherwise being turned off.
Dispenser: A device that will dispense a single item when activated. If it’s containing a fluid, projectile, or entity (lava, splash potions, spawn eggs), it will fire the item instead (that is, it can pour streams of lava or shoot out potions).
Dropper: Identical to the dispenser, but this time it will dispense its contents in item form no matter what (a bucket of lava would create a stream if poured out of a dispenser, but for a dropper, it just ejects the bucket of lava itself).
Noteblock: A musical block that will play a note when powered by a signal. The pitch can be set by hand, and the instrument that it mimics depends on what block it’s placed on. You can also play it manually.
Activator Rail: When activated, it performs a certain task on any minecart that rolls over it. Entities such as mobs will be automatically ejected from the cart, TNT carts will be lit, etc. It also disables hopper carts’ ability to take in items. In order to enable a hopper cart, have it roll over a deactivated rail.
TNT: A block of explosives that detonates when set on fire or receives a signal. This can even be done using Fire Aspect weapons or Flame arrows, and the resulting explosion is enough to ignite nearby TNT as well.
Circuitry
Redstone Repeater: a device that strengthens any redstone signal that passes through it back to the max 15 blocks, regardless of the signal strength beforehand. It can also be used to delay signals to up to 4 ticks, which is achieved by interacting with the repeater.
Redstone Comparator: A device that has many uses, it can maintain signals, measure whatever’s in front of it, compare two different signals, or subtract two different signals. You can interact with it to toggle between two modes:
When the lone torch is OFF, the Comparator is COMPARING signals.
When the lone torch is ON, the Comparator is SUBTRACTING signals.
When the two back torches are ON, the Comparator is SENDING a signal.
When the two back torches are OFF, the Comparator is NOT sending a signal
When comparing, the device takes two different signals, and based on which one overpowers the other, will decide whether or not it will send a signal through. When subtracting, the comparator subtracts the strength of the weaker signal from the stronger one, and then outputs the difference through the other side.
A comparator also measures the state of certain blocks, primarily storage ones. Similar to the Detector Rail, it will output a signal based on how full a storage block is (cauldron, chest, etc). It evens works with single-block storages, such as Item Frames or End Portal Frames.
Work In Progress because holy shit does this game have a lot of stuff in it