A chordal graph is a type of graph in which every cycle of four or more vertices has a chord. A chord is an edge that connects two non-adjacent vertices in the cycle. This property ensures that the graph does not contain any induced cycles of length greater than three, making it a useful structure in various applications, such as computer science and optimization. Chordal graphs are also known as perfect graphs because they exhibit certain optimal properties related to graph coloring. They can be efficiently recognized and have applications in areas like database theory and network design, where understanding the relationships between elements is crucial.