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Let $G_1$ and $G_2$ be copies of a graph $G$, and let $f:V\left(G_1\right)\to V\left(G_2\right)$ be a function. Then a functigraph $C(G,f)=(V,E)$ is a generalization of a permutation graph, where $V=V\left(G_1\right)\cup V\left(G_2\right)$ and $E=E\left(G_1\right)\cup E\left(G_2\right)\cup \{uv:u\in V\left(G_1\right),v\in V\left(G_2\right),v=f\left(u\right)\}$. In this paper, we study colorability and planarity of functigraphs.