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  "body": "\n## Summary\n\nThe stable homotopy category has [[spectra|1GHF4EKBXS]] as objects and homotopy classes of maps of spectra as morphisms.\nIn it the stable weak equivalences are made invertible.\nIn it the suspension functor is an equivalence, every morphism set is an abelian group, and cofibre sequences are also fibre sequences.\nIt is a triangulated category with a symmetric monoidal smash product, and it is the setting of [[stable homotopy theory|545EV0W4CE]].\n\n## Explanations\n\n### L1 human\n\nSpaces can be suspended, but not desuspended.\nIn the stable homotopy category every object can also be desuspended, so shifting up and down are inverse operations.\nMaps between objects form abelian groups, much as linear maps between vector spaces do.\nFor two finite CW complexes, the maps between their suspension spectra are exactly the stable homotopy classes of maps between them.\nFor example, the maps from the sphere spectrum to itself form the group $\\Z$, given by degree.\n",
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