A cubic graph is a type of graph in mathematics where each vertex has a degree of three, meaning that each vertex is connected to exactly three edges. These graphs can be used to model various real-world situations, such as network connections or molecular structures. Cubic graphs can be classified into different types, including regular graphs and planar graphs. They often exhibit interesting properties, such as symmetry and connectivity, making them a subject of study in graph theory. Examples of cubic graphs include the Petersen graph and the 3-dimensional cube.