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  "body": "\n## Summary\n\nA ring spectrum is a [[spectrum|1GHF4EKBXS]] with a multiplication and a unit that satisfy the ring axioms up to homotopy.\nIt is the stable analogue of a ring, with the [[sphere spectrum|14CGGHA85T]] in the role of the integers.\nThe cohomology theory represented by a ring spectrum has cup products, so its values on spaces are graded rings.\n\n## Explanations\n\n### L1 human\n\nA ring is a set with a multiplication that has a unit and is associative.\nA ring spectrum is the same idea one level up: a spectrum $E$ with a map $E \\wedge E \\to E$ and a unit map from the sphere spectrum.\nOrdinary cohomology with coefficients in a ring, complex K-theory and complex cobordism all come from ring spectra.\nThis is why in each of them one can multiply two cohomology classes.\n",
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