The Laws of Minecraft Redstone
Every Minecraft redstone mechanism has a different set of properties that determine how it acts. You should understand the relationships between their properties. After you work with redstone for a while, the form and function of your tools can become fairly intuitive. Until then, you can use this information to figure out what options are available to you, and how you want to assemble your devices.
The laws of power production
Here, you can see every block that can provide redstone power. The devices are surrounded by yellow and red blocks indicating the spaces that those devices can power: Yellow blocks indicate spaces where other devices can be powered, and red blocks indicate spaces where both devices and blocks can be powered. (Any solid block can be powered in this way, causing it to power all adjacent devices.)
You can use this as a guide for constructing redstone machines more intuitively, as long as you remember the following rules:
To use one device to power another, place the device in one of the yellow or red spaces.
To split a redstone current into several different outputs, place a solid block in a red space, and place some devices next to the block.
Don’t put a block that can be powered in a device’s yellow or red space, and don’t put a block in a device’s red space, unless you want it to be powered by that device.
The yellow and red spaces have been added for your convenience; they don’t appear in your game. You should learn to visualize redstone connections and understand what links to what; this is an important skill to practice if you want to design quickly and efficiently.
The laws of power reception
If a device can be powered by redstone current, it has rules for how it can be powered. Here, you can see every device that can be affected by redstone power.
Each block has one or more blue blocks adjacent to it (made of glass or wool) — these blue blocks indicate the direction from which the device can be powered. In other words, a device can be powered only if the power source is in the place of one of the blue blocks.
This is a useful guide for connecting redstone devices. As long as you recall how each block can be powered, you should have no trouble knowing how to integrate them into your machines.