What is a closed walk?

A closed walk specifically refers to a sequence of edges in a graph that begins and ends at the same vertex. This means that you can traverse around the graph, following the edges, and return to the starting point, forming a loop. The concept of a closed walk is essential in various areas of graph theory, as it helps in understanding cycles and connectivity within graphs.

In contrast to this definition, other types of walks could allow for the use of all edges, restrict the use of repeated edges or vertices, or involve paths that do not return to the initial vertex. Hence, the characteristic of starting and concluding at the same vertex is central to defining a closed walk.