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  "body": "\n## Summary\n\nA skeleton of a [[category|A2DE66937D]] $\\mathcal{C}$ is a [[full subcategory|V3BFGKBJF7]] that contains exactly one object from each isomorphism class of objects of $\\mathcal{C}$.\nUnder the axiom of choice every category has a skeleton, and the inclusion of the skeleton is an [[equivalence of categories|K7A04ZBD92]].\nSo a skeleton is a smallest model of the category up to equivalence, and two categories are equivalent exactly when their skeletons are isomorphic.\n\n## Explanations\n\n### L1 human\n\nMany objects of a category are copies of each other up to isomorphism.\nA skeleton keeps one representative of each kind and throws the copies away, while keeping all arrows between the representatives.\nFor finite sets, the sets $\\set{1, \\dots, n}$, one for each $n \\ge 0$, form a skeleton.\nNothing essential is lost, because every finite set is in bijection with exactly one of them.\n",
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