Redstone is the material that powers many of the crazy creations you can make in Minecraft. From flying machines to automatic farms, redstone plays a vital role in powering Minecraft machines.
Thus, knowing which blocks redstone can pass through and which blocks to use when building a machine is crucial to gameplay as each has its use and conditions for emitting a signal.
Connecting Inputs & Outputs
Before jumping into the types of inputs and outputs, it's necessary to understand how redstone works, and where inputs and outs come into play.
Simply, redstone works similarly to electricity, where a signal travels from an input to an output to create or activate different devices. For example, redstone can be used with a lever to power on a lamp, just like a light switch used to turn on a light.
And that's just the tip of the iceberg...
Redstone Inputs
As mentioned above, redstone inputs are power sources, such as blocks or items that create a redstone signal when interacted with, including levers, buttons, and pressure plates.
Here is a rundown of the different redstone inputs.
Redstone Torches
Redstone Torch provides a constant source of redstone power (and can be turned off through various methods).
Redstone torches are similar to blocks of redstone because they always start "on." They can be inverted, or turned off, if another input is powering their space.
You can see the redstone torch in the second image isn't glowing because the block of redstone has inverted it.
Levers
Levers are like switches in real life—they provide power when turned on, and none when turned off.
Buttons
Buttons provide a quick pulse of power before turning off. They provide power for a few moments, then turn off.
Daylight Sensors
Daylight sensors are a special redstone input that emits a redstone signal when it is daylight outside. Something to note is that the sensor needs to be placed outside to work.
Right-clicking on it "inverts" the sensor, making it emit a signal when it is night/dark instead!
Tripwire Hooks
Two tripwire hooks need to placed on walls with string placed between them in order to work. When working, a signal is emitted when something (block, mob, player) touches the string. These can be used to make great traps!
Detector Rails
Detector rails function similarly to the tripwire, but requires no string and only works with minecarts. Thus, detector rails are useful for opening secret doors when on long minecart rides (and when you want to repeat something repeatedly).
Redstone Outputs
Now that we know how different redstone inputs work, it's time to learn about the outputs! What can result from those redstone connections?
Iron Doors and Trapdoors
Unlike regular doors, iron doors and trapdoors require power to open and close, but they are much stronger than regular doors.
Redstone Lamps
Redstone lamps make light when powered.
Pistons
Pistons will "push" when they get power and move back when they don't. They can move blocks and are useful for a number of different devices.
Sticky Pistons
Sticky pistons are similar to normal pistons because they push blocks when powered, but they will bring blocks back with them instead. Meaning, the block will "stick" when not powered.
Powered Rail
Powered rails give power and push the minecarts that move over them. (And if you do it right, you can make them go forever!)
Droppers
Droppers will store items and drop them for you to pick up when powered. Pretty handy!
Dispensers
Instead of dropping items for you to pick up like droppers, dispensers will fire items like arrows (and hard enough that they do damage)!
Note Blocks
Note blocks play a musical note when they are powered. The note played depends on the type of block that the note block is on. For instance, a note block on wood will make a different sound than a note block on grass.
Build Away!
With this knowledge, we can think bigger and better, and even use many inputs or outputs in a single device or build several devices that use different functions!
Remember—redstone dust trails can only go out 15 blocks before losing power. The farther dust trails go, the less power is sent to the output block.
Happy building!