Graph as cell complex

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I am reading a paper about graphs. In this paper, authors wrote "we view infinite graph as cell complex with usual topology". All graphs are infinite here.

I know that we can consider graphs with following topology:

An arc $A_i$ is space homeomorphic to the unit interval [0,1].

Graph is a space $X$ that is the union of a collection of subspaces $A_i$ each of which is an arc, such that

(1) The intersection of two arcs $A_i\cap A_j$ is either empty or consists of a single point that is an end point of each.

(2) The toplogy of X is coherent with the subspaces $A_i$.

I am not familiar with cell complex and its topology. But, my question is Is the topology of cell complex as graph the same as with above topology?

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Yes, they are the same. For a quick explanation, I'll paraphrase Hatcher's discussion from his book Algebraic Topology.

In terms of CW complexes, a graph is a space $X$ obtained from a discrete set $X^0$ be adding a collection of 1-cells $e_\alpha$.

In non-CW speak, this means $X$ is formed from the disjoint union of $X^0$ with closed intervals $I_\alpha$ by identifying the two endpoints of $I_\alpha$ with points in $X^0$. Here, the points in $X^0$ are the vertices of the graphs and the 1-cells $\{e_\alpha\}$ are the edges of $X$ (note that in this definition the edges does not include it's endpoints, so the closure $\overline{e_\alpha}$ of an edge $e_\alpha$ is the same as an arc $A_\alpha$ using your notation).

The usual topology is the quotient topology $X$ inherits from the disjoint union $$X^0 \coprod_\alpha I_\alpha$$ That is, a subset of $X$ is closed iff it intersects each $\overline{e_\alpha}$ in a closed set in $\overline{e_\alpha}$. So yes, the two definitions are equivalent.