What is the difference between a board game, a wargame and a tabletop RPG?
What the players are doing — competing within fixed rules, simulating a conflict, or collaboratively telling a story — and each carries different expectations about winning, length and preparation.
Board game. A defined set of rules, a fixed end condition, and usually a winner. Play sits within the rules, and the game state is fully visible on the table. Sessions typically last from twenty minutes to a few hours, and setup is minimal.
Wargame. Simulates military conflict, historical or fictional, usually with miniatures on a terrain board or with counters on a hex map. Distinguishing features:
Simulation intent — the rules aim to model something, so they are frequently far more detailed than a board game needs.
Asymmetric forces and scenario-based objectives rather than identical starting positions.
Substantial preparation — army lists, assembling and painting miniatures, terrain. For many players this is a large part of the appeal and the hobby extends well beyond playing.
Long sessions, sometimes across multiple days for large historical games.
Tabletop roleplaying game (TTRPG). Players each control a character and describe what that character does; a game master describes the world, plays everyone else, and adjudicates outcomes, usually with dice resolving uncertainty.
The defining difference: the rules do not enumerate the possible actions. In a board game you may do the things the rules permit. In an RPG you may attempt anything you can describe, and the system resolves whether it works. That open-endedness is the whole point.
Usually no winner, and play continues across a campaign of many sessions with continuity between them.
The blurred edges. Legacy board games have persistent campaigns; many modern board games are cooperative; some RPGs are highly tactical and grid-based; and skirmish games sit between wargames and board games.
Euro versus Ameritrash is the other distinction worth knowing within board games. Euro games favour indirect competition, resource management, minimal luck and no player elimination. Ameritrash — used affectionately — favours theme, direct conflict, dice and dramatic swings. Most modern designs borrow from both, and the labels are now descriptive rather than tribal.