The most zoomed out scale are strategic games. An easy rule of thumb to know if you’re playing a strategic game is to check and see if you’re playing an entire country. Strategic games often simulate a whole war or at least a complete theatre. Think of games like World in Flames, Third Reich, or Triumph and Tragedy. The unit scale is often full armies, the time is months or seasons, hexes can be 100 miles across or more. In addition, strategic games often have political elements not found in lower level games, and sometimes have options for production and technology.
Confusing matters, there are strategic games that have operational elements, or operational games that have tactical elements. And there’s not a sharp divide between classes, so with some games, it’s a little tricky to pigeon-hole its exact type. But I hope this gives you enough to have a better sense of what these scales are all about.
