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  "body": "\n## Summary\n\nIn model theory, a type is a set of formulas in some free variables that is consistent with a theory.\nIt describes the possible behaviour of a tuple of elements.\nA complete type gives a full first-order description of a tuple: every formula or its negation belongs to it.\nA type is realized in a model when some tuple of the model satisfies all its formulas, and omitted otherwise.\nTypes are the basic tool for comparing models, and counting them leads to [[saturated models|RMTZ5J64FX]], categoricity and stability.\n\n## Explanations\n\n### L1 human\n\nA type is a list of properties that an element could have, written in the language of the theory.\nFor example, take the ordered field of real numbers and the list \"$x \u003e 1$, $x \u003e 2$, $x \u003e 3$, and so on\".\nIt is a type, because every finite part of it is satisfied by some real number.\nNo real number satisfies the whole list, so $\\R$ omits this type.\nIn a nonstandard model of the reals the type is realized by an infinitely large element.\nSo types record which kinds of elements a model has and which it is missing.\n",
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