A directed graph, also known as a digraph, is a collection of nodes connected by edges that have a specific direction. Each edge points from one node to another, indicating a one-way relationship. This structure is useful for representing various systems, such as social networks, where relationships are not always mutual. In a directed graph, the nodes represent entities, while the directed edges illustrate the connections or interactions between them. For example, in a directed graph representing a website, nodes could be web pages, and directed edges would show links from one page to another, highlighting the flow of information.