Suggest an editImprove this articleRefine the answer for “What is an undirected graph?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)An **undirected graph** is a graph in which **edges have no direction**. **Key point:** in an undirected graph, all connections are two-way, direction does not matter.Shown above the full answer for quick recall.Answer (EN)ImageAn **undirected graph** is a graph in which **edges have no direction**. Formally: A graph **G = (V, E)**, where each edge is an **unordered pair of vertices** {u, v}. This means the connection between **u** and **v** is mutual: **u ↔ v**. --- ### Main idea If vertices are connected, movement is possible **in both directions**. That is, the edge {A, B} means a connection both as **A → B** and **B → A** at the same time. --- ### Example If there are vertices **A**, **B**, **C**, and edges: - **A-B**, - **B-C**, then you can go from **A to C** and back, through **B**. --- ### Typical applications - Friendship on social networks (both added each other). - Roads between cities, if traffic is two-way. - Interaction networks, where the connection is mutual. --- **Summary:** in an undirected graph, all connections are **two-way**, direction does not matter.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.