Cographs, or complement-reducible graphs, are a special class of graphs that can be constructed from a single vertex by repeatedly applying two operations: disjoint union and complementation. They are characterized by the absence of induced paths of four vertices, making them a unique subset of graph theory. Cographs are also known for their efficient representation and can be used in various applications, including computer science and network design. One of the key properties of cographs is that they can be represented using a binary tree, where each leaf corresponds to a vertex in the graph. This representation allows for efficient algorithms to perform operations such as graph traversal and connectivity checks. Cographs play a significant role in graph theory and have connections to other concepts like cliques and independent sets.