This page is inspired by S. John Ross’ RPG Lexicon as well as various collections from John Kim’s massive RPG site, such as the System Design series, as well as many other uncountable sites, discussions, articles, etc.
The following is more so a lexicon for how I use these terms and more a guide to understanding what I mean when I say certain things on my blog. I don’t propose these to necessarily be universal or prescriptive, and you may disagree with any number of these. I will try to link to relevant articles where appropriate.
last updated Sunday December 1st, 2024
Artifact: The “physical” components of a game – the pieces, dice, rules text, character sheets, etc. Also referred to as object-of-play.
Diegetic: An element-of-play that exists within the game world. An example would be a character’s sword, which they may use to swing around. Note that I often dislike this term as it is widely used incorrectly – most use cases of this word in the RPG community aims at something more akin to “de-abstracted.” For this reason I often say “in-fiction” instead of diegetic.
Element-of-Play: Another term for ludeme.
Extradiegetic: An aspect of the game that exists in the world of the players, outside of the world of the characters. An example include the dice used to play, character sheets, or even the specific words and numbers written on a character sheet.
Kriegsspiel: A family of wargames, originally developed by the Prussian Army to teach battlefield tactics to officers.
Free Kriegsspiel: An approach to the Kriegsspeil family of wargames that threw out the necessity of any particular rule, instead leveraging the referee’s experience and judgement for adjudicating situations. This contrasted with Rigid Kriegsspiel.
Free Kriegsspiel Revolution (FKR): A role-playing movement focused on traditional role-playing games, with a primary focus on high-trust gaming, playing worlds, and the referee using rules as tools, rather than a world’s internal physics system or a replacement for a social contract. The name was derived from a post by Mike Mornard, who had observed that he did not identify with the Old School Renaissance, and that he felt too many gamers focused far too much on the specific rules rather than the play at hand. He noted that Free Kriegsspiel’s use of the referee was a killer feature that led to role-playing games.
Ludeme: An element-of-play. This contrasts with artifacts or objects-of-play. The often-cited example is the L-shaped movement procedure of a Knight in Chess is a ludeme (while the Knight piece is an object-of-play).
Mechanic: In game design and studies, mechanic is a somewhat loaded and confusing term, being applied many different definitions, so I typically try to avoid it. Often when people use it, they are referring to something like “mechanism, but only ones for which there are explicit rules for.” Mechanics are also sometimes used to refer to artifact or objects-of-play: the board and pieces in Chess, for example. I typically try to avoid the term, but it pops up in a number of discussions, and I fall back into a bad habit of using it, so when I do – I almost always mean mechanism.
Mechanism: Both the rules of play, as well as the ludemes of a game.
New School Revolution (NSR): One of the many “post”-Old-School-Renaissance movements, originally focused on designing and playing games in the play-styles of modern OSR games, without caring much about compatibility with classic Dungeons & Dragons, or any other classic role-playing game. 1
Object-of-Play: Another term for artifact.
Old-School Revolution/Renaissance (OSR): The old school renaissance (sometimes revolution, rules, etc.) is a series of communities, some present and some past, that focused on discussing, playing, and publishing for classic versions of Dungeons & Dragons, as well as some other classic games from the seventies and eighties. The OSR was never centralized, so wide debates range over whether or not certain games are included in the movement, if the OSR is “dead” or not, how much play-style matters, etc.
Pen/Pencil-and-Paper Role-Playing Game: Another name for tabletop role-playing games. While pens (or pencils) and paper are often included, their presence are not necessary, especially in the digital age.
Rigid Kriegsspiel: A game in the Kriegsspiel family that uses strict adherence to rules over referee rulings.
Role-Playing: The act of participating in a role-playing game. 2
Role-Playing Game (RPG): A game where players take on the role of character(s) inhabiting a fictional world (if even just a fictionalized version of our world). On this blog I almost always refer to tabletop role-playing games, and specifically traditional role-playing games.
Rule: A clear instruction of “how to play.” This is often used interchangeably with “ludeme” although I often differentiate the two in my head – a rule is really just a prescription of how to enact a ludeme, but ludemes can exist outside of rules.
Ruling: An ad-hoc adjudication made by a referee during a game, either for a situation no rules cover, or overriding rules that a referee believe will produce dissonant fictional results. Rulings often become rules, either when transcribed by the group, or as a form of communal memory.
Rules Text: The artifact containing the written rules of a role-playing game, which may also include such things as information regarding the fictional setting, inspirational media, fiction, etc.
System: The whole process that the table uses to determine “what happens” in game. People often use this to refer to the mechanisms of play and/or the rules text, although system is truly much larger than that.
Table: I often use this term to mean “the group playing a role-playing game.” Although given that there are also physical tables that games are played at, and things such as random tables, I should probably consider using a less ambiguous term.
Tabletop Role-Playing Game (TTRPG): An RPG played around a tabletop, whether physical or virtual. While the use of a table is not strictly necessary, the term denotes a contrast from such things as Live Action Role-playing Games (LARPs) or video games that include some component of role-playing.
Tactical Infinity: The ability for players to direct their characters to apply any action, or “tactic,” per adjudication by the referee. This is one of the defining features of trad games. 3
Trad: Shorthand for traditional role-playing game.
Traditional Role-Playing Game: A form of tabletop role-playing game where one player takes on the role of a Referee or Game Master, representing the rest of the world outside of the players’ characters, responding to their actions with what happens and adjudicating situations as they see fit. Games that lack referees or have mechanics for players shifting roles contrast with this category of play.