Let $\mathrm{ G}$ be a subgroup of the symmetric group $\mathfrak S(U)$ of all permutations of a countable set $U$. Let $\overline{ \mathrm{ G}}$ be the topological closure of $\mathrm{ G}$ in the function topology on $U^U$. We initiate the study of the poset $\overline{ \mathrm{ G}}[U]:=\{ f[U]\mid f\in \overline{ \mathrm{ G}}\}$ of images of the functions in $\overline{ \mathrm{ G}}$, being ordered under inclusion. This set $\overline{ \mathrm{ G}}[U]$ of subsets of the set $U$ will be called the \emph{ poset of copies for} the group $\mathrm{ G}$. A denomination being justified by the fact that for every subgroup $\mathrm{ G}$ of the symmetric group $\mathfrak S(U)$ there exists a homogeneous relational structure $R$ on $U$ such that $\overline G$ is the set of embeddings of the homogeneous structure $R$ into itself and $\overline{ \mathrm{ G}}[U]$ is the set of copies of $R$ in $R$ and that the set of bijections $\overline G\cap \mathfrak S(U)$ of $U$ to $U$ forms the group of automorphisms of $\mathrm{ R}$.
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