HOI4 Glossary of Terms — Cuartel General

The HOI4 community uses a lot of acronyms and jargon. Here are the ones you'll run into most while reading these guides, playing online, or talking with other players on forums and Reddit, explained quickly.

General

HOI4Hearts of Iron IV: The game's name. Almost nobody writes it out in full.
Focus / focus tree: Each country's national decision tree: activating a focus unlocks events, bonuses or new options.
PPPolitical Power: The currency you spend to activate focuses, hire ministers, or make certain political decisions.
Ironman: A mode with no manual saving: the game autosaves and you can't reload a previous save. Mandatory for achievements, a bad idea for your first game.
Historical / non-historical AI: An option when creating a game that decides whether the AI roughly follows the real World War II script or improvises on its own.
DoWDeclaration of War: The moment two countries officially go to war, usually after completing a wargoal or answering a call to arms from your faction.
GCGrand Campaign: What the community calls the historical scenario starting on January 1st, 1936 — the starting point for almost every game.

Economy and Research

Manpower: Pool of population available to recruit divisions. It runs out if you recruit faster than it regenerates.
Production efficiency: A military factory's real output against its theoretical maximum. See the production guide.
XPExperience (army / navy / air force): Points you earn through research, training or combat. Spent on equipment variants or template upgrades.
MIOMilitary Industrial Organization: Manufacturer consortiums that improve with use, introduced in the Arms Against Tyranny DLC. See the DLC guide.

Combat

Combat width: The "space" a division takes up in a battle. See the dedicated guide.
OrganizationOrg: How long a division can keep fighting before it gives out. Hit zero and it retreats or collapses.
CASClose Air Support: Aircraft that bomb enemy divisions directly in combat. See the air warfare guide.
Command capacity: The number of divisions a general or field marshal can lead without penalty. See the military command guide.
Doctrine: Your nation's land combat philosophy (Mobile Warfare, Superior Firepower, etc.). See the doctrines guide.
ATAnti-Tank: A battalion or piece of equipment built to punch through enemy armor. Comes up in every division template conversation.
EngEngineer company: A support company that improves entrenchment and makes river crossings or fort assaults easier.
SPSelf-Propelled: Prefix for equipment mounted on its own powered chassis (SP Art, SP AA...) — pricier than the towed version, but faster and better armored.
SRStrategic Redeployment: Speed bonus divisions get when moving by rail between two zones that are already connected and under your control.

Diplomacy and Occupation

World tension: Global gauge that sets how much room you have to act aggressively without penalty. See the diplomacy guide.
Faction: Group of countries committed to defending each other in case of war.
Wargoal: The paperwork — and the waiting time — needed to declare war on another country "legitimately" within the game.
Compliance / Resistance: Occupation mechanics introduced in La Résistance: how much the population accepts your control, and how much it organizes to undermine it. See the DLC guide.
NAPNon-Aggression Pact: A bilateral agreement that lowers the odds the other country attacks you while it lasts. See the diplomacy guide.
SCWSpanish Civil War: The 1936-1939 conflict already underway at the start of the historical game if you play or intervene in Spain.
WCWorld Conquest: The unofficial goal — no achievement attached — of annexing or subjugating the entire planet in a single game.

Community Jargon

AARAfter Action Report: A player's account of a played game, shared with screenshots and commentary, common on forums and Reddit.
IIRCIf I recall correctly: A hedge used when citing a number or mechanic from memory without checking it first.
IMO / IMHOIn my (humble) opinion: Marks what follows as a personal opinion, not a verified fact.
ATMAt the moment: Usually refers to a temporary state of the game or of a specific playthrough.
MMMicromanagement: How much manual attention a mechanic demands. "Heavy MM" means you have to stay on top of it constantly.
OOBOrder of Battle: The full makeup of an army: which divisions, grouped how, under which command.