Minecraft wiki entry for Redstone_computers, associated text: The CPU follows a cycle four steps, fetch, decode, execute and (sometimes) stores to perform instructions. The CPU first fetches the instruction from RAM, decodes what it means (the instruction will most likely be a number, and the CPU must find out what number it is), and once it understands what the instruction is, it will perform that action. This sometimes requires the data to be put back into the storage, therefore it will store the data. The cycle is then repeated.