Notation 1.4.1.2. Let $\operatorname{\mathcal{C}}$ be an $\infty $-category. We will often write $X \in \operatorname{\mathcal{C}}$ to indicate that $X$ is an object of $\operatorname{\mathcal{C}}$. We use the phrase “$f: X \rightarrow Y$ is a morphism of $\operatorname{\mathcal{C}}$” to indicate that $f$ is a morphism of $\operatorname{\mathcal{C}}$ having source $X$ and target $Y$.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$