Block update

A block update is an in-game mechanism that occurs when a block is modified in some way. Limited to the computing power of a computer, the game can not process all blocks at all times, which is why the game needs such mechanism. When a block changes (due to a player, an entity, or a chunk tick, etc.), it notifies nearby blocks that they should check if they need to respond to the change.

In Java Edition, there are two main types of block updates: post placement (PP) and neighbor changed (NC).

This article uses the priorities listed in the table below to categorize the various block updates. However, keep in mind that these values are not actually present in the game's code.