## 94.2 Notation

In this chapter we fix a suitable big fppf site $\mathit{Sch}_{fppf}$ as in Topologies, Definition 34.7.6. So, if not explicitly stated otherwise all schemes will be objects of $\mathit{Sch}_{fppf}$. We will always work relative to a base $S$ contained in $\mathit{Sch}_{fppf}$. And we will then work with the big fppf site $(\mathit{Sch}/S)_{fppf}$, see Topologies, Definition 34.7.8. The absolute case can be recovered by taking $S = \mathop{\mathrm{Spec}}(\mathbf{Z})$.

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