Glossary

How to use this page: one definition per term, no argumentation. Terms marked (this book) are analytical concepts coined in this book; the rest are community or official usage.

1World and data

Block: the basic unit of the world, a cell of roughly one cubic meter; the object of all building, breaking, and interaction.

Voxel: a three-dimensional "volume pixel"; this book uses the word for the manipulable integer grid, not for any rendering technique.

Air: a real block. Empty space still occupies a cell of data — which is why the world can be recorded cell by cell.

Chunk: the world's unit of spatial and read/write slicing, a 16×384×16 column; loading, saving, and simulation are all settled by it.

Section: a 16×16×16 sub-cube inside a chunk, the unit of measurement for storage and palettes.

Palette: each section keeps one "table of kinds" and blocks store only an index into it — the workhorse of same-kind compression.

Block state: a block's mutable properties (facing, water level, lit or not); after the 1.13 Flattening it replaced the old numeric metadata.

Block entity: a block that carries private data (chest, furnace, sign) — it has data, keeps accounts, and does not walk.

Entity: anything "positioned in the world and moving by itself": mobs, dropped items, boats, arrows. Computed every tick — the first tax on performance (this book's usage).

Component: a named, customizable property of an item or block; the landed form of "named lists beat free-form fields".

NBT: Named Binary Tag, a tagged binary data format; the world's universal storage box.

Namespace: the prefix of every piece of content's full name (minecraft: and your own) — the address-plate system that prevents collisions.

DataFixerUpper: Mojang's open-source migration library: it translates old-version data to new versions layer by layer, additive only, never subtracting.

Obfuscation: the release-time pass that replaces class and method names with gibberish; officially removed as of October 2025.

Far Lands: terrain in old versions that shattered far from spawn when floating-point precision ran out — the engineering tell behind "infinite", enshrined by the community as a pilgrimage site.

2Time and simulation

Tick: the time step of simulation. Java Edition runs 20 ticks per second, each with a 50-millisecond budget — the world's clock.

TPS: ticks per second. When TPS drops the frame rate doesn't stutter — the world slows down; the furnace genuinely runs slower.

Scheduled tick: a block's reserved "must-do, on time" item: water flow, falling sand, fire spread.

Random tick: every tick, blocks are sampled at random for growth and decay; the world's sense of being alive is supplied here.

Quasi-connectivity: the implementation quirk by which a piston can be activated by a power source "one block above"; MC-108, closed as "works as intended" — the community has since treated it as bedrock (Java Edition only).

BUD: Block Update Detector — a switch built on the suspended state of "powered but not notified"; later officially adopted as the observer block.

Cascading updates: the graph computation where one cell's change triggers its neighbors and the neighbors trigger theirs; the common breeding ground of lag and duplication bugs alike.

Simulation distance / render distance: the former governs how far away the world keeps "running", the latter how far away it stays "visible"; separated since 1.18.

3Extension and ecosystem

Mod: an extension that modifies the client and/or the server program itself; it can add new systems and usually requires a loader.

Plugin: an extension that modifies only the server, so a vanilla client can join (the Bukkit/Spigot/Paper lineage); it rewrites "this server's law".

Datapack: the official data-layer extension, travels with the save; it can fill registry slots but cannot build new mechanics. Java Edition only.

Resource pack: the official layer that swaps appearance without touching rules: textures, sounds, models.

Add-on: Bedrock Edition's data-extension format (resources + behavior + scripts), eligible for Marketplace review.

Loader: the framework that manages mod installation and conflicts: the Forge, Fabric, NeoForge lineage.

Mixin: a bytecode-weaving technique that stitches a small piece of logic into official methods; the foundation of lightweight mods.

Event listener: the mechanism by which a plugin weighs in before events such as "block broken" actually fire; land claims, economies, and minigames all grow out of this one incision.

Modpack: a curated work that tunes dozens of mods into a coherent whole; its author is called "the third layer of authorship".

Vanilla: Minecraft with no modifications installed; the word had to be invented because the mod ecosystem flourished.

4Editions and products

Snapshot: the public test build preceding every Java Edition release; Bedrock's counterpart is called a Preview.

Bedrock Edition: the C++ implementation shared by the non-Java platforms; unified step by step out of Pocket Edition.

Marketplace: Bedrock's built-in official content store; partner-and-review based, settled in Minecoin.

Realms: the official monthly-fee rental of small servers; a byword for peace of mind, deliberately weaker than third-party hosting.

Semantic fork: the same mechanic behaving differently in the two editions (combat cooldown, say); brand debt more lethal than a performance gap (this book's usage).

5Community and analysis (including this book's concepts)

Griefing: destroying other people's work for pleasure; a product of the open world's default political state.

Pay-to-win: buying advantages that distort balance with money; the red line drawn by the 2014 EULA.

Misusable system (this book): a system where three things hold at once — it delivers physics rather than a play list, correct usage is invented by the community and fed back into the rules, and misuse goes unpunished.

Interest management (this book): the institution that allocates simulation resources by "who is watching"; vanilla's outstanding debt, and the core question of the rewrite by which the community makes it up.

Causal unit (this book): a strict-order settlement region bounded by a connected graph; interest-driven parallelism must not come at its expense.