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  "body": "\n## Summary\n\nBredon cohomology is a cohomology theory for spaces with an action of a group $G$.\nIts coefficients are not one group but a system of groups, one for each orbit type $G/H$.\nIt is computed from the cell structure of a $G$-CW complex and keeps track of the fixed point sets $X^H$ of all subgroups $H$.\nIt is the basic ordinary cohomology theory of equivariant homotopy theory, and the obstructions of equivariant obstruction theory lie in it.\n\n## Explanations\n\n### L1 human\n\nWhen a group acts on a space, some points are moved freely and others are fixed by part of the group.\nBorel's [[equivariant cohomology|C7MZ3SFGYF]] uses one coefficient group for the whole space.\nBredon cohomology looks separately at the points fixed by each subgroup and lets the coefficients depend on that subgroup.\nFor example, for a group acting on a single point, it returns the coefficient group attached to the whole group $G$.\n",
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