Sim the Game, Not SIM Cards or The Sims

If you searched for “Sim” and landed here, you may have meant one of three completely different things. This page is about Sim the game — the 1969 pencil-and-paper strategy game by Gustavus Simmons that Triad brings online. It is not a SIM card, and it is not The Sims. Here is how to tell them apart.

Sim the Game vs the SIM Card

A SIM card — short for Subscriber Identity Module — is the small chip that stores your identity on a mobile network. Sim the game has nothing to do with phones. It is a two-player game played by drawing coloured lines between six dots, where the first person to complete a triangle entirely in their own colour loses. The two only share a spelling: the game was named after the mathematician Gustavus Simmons, while the SIM card is an unrelated telecoms acronym that became common decades later.

Sim vs The Sims (and Other Simulation Games)

The Sims is a best-selling life-simulation video game franchise, and “sim” is also shorthand for simulation games in general (flight sims, city-building sims, and so on). Sim the game is the opposite of a sprawling simulation: it is an abstract strategy game with three rules and no theme at all. Where a simulation models a world, Sim models nothing — it is pure structure, six dots and the lines between them. If you want the deep-but-tiny pencil game rather than a simulator, you are in the right place.

Where the Name Comes From

The game predates both other meanings. Gustavus Simmons, a cryptographer at Sandia National Laboratories, introduced Sim in the Journal of Recreational Mathematics in 1969 — before SIM cards entered everyday language and before The Sims existed. The name is simply a contraction of Simmons. Over the following decades the word “sim” was claimed by phones and video games, which is much of why this elegant little game slipped into obscurity. The fuller story is in the history of Sim.

So What Is the Sim Game?

In one sentence: Sim is a two-player game on six dots where you draw lines in your own colour and lose if you complete a triangle. It can never end in a draw — a fact that follows from Ramsey theory, specifically R(3,3) = 6. For the full rules, the maths, and the strategy, start with what is Sim, or just play Triad and learn by doing.