A complete graph is a type of graph in which every pair of distinct vertices is connected by a unique edge. In simpler terms, if you have a set of points (or vertices), a complete graph includes a line (or edge) between every possible pair of those points. This means that if there are n vertices, the complete graph will have \fracn(n-1)2 edges. Complete graphs are denoted as K_n, where n represents the number of vertices. For example, K_3 is a complete graph with three vertices, forming a triangle. Complete graphs are important in various fields, including graph theory and network design, as they help in understanding connectivity and relationships between points.