Definition 7.12.3. Let $\mathcal{C}$ be a site whose topology is subcanonical. The Yoneda embedding $h$ (see Categories, Section 4.3) presents $\mathcal{C}$ as a full subcategory of the category of sheaves of $\mathcal{C}$. In this case we call sheaves of the form $h_ U$ with $U \in \mathop{\mathrm{Ob}}\nolimits (\mathcal{C})$ representable sheaves on $\mathcal{C}$. Notation: Sometimes, the representable sheaf $h_ U$ associated to $U$ is denoted $\underline{U}$.

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