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In graph theory, a graph, also called a network, is a collection of points together with lines that connect some subset of the points.

Graph is a college-level concept that would be first encountered in a discrete mathematics course covering graph theory.


Complete Graph: A complete graph is a network in which every pair of vertices is connected by an edge.
Connected Graph: A connected graph is a network for which there is a path between any pair of vertices.
Cycle Graph: A cycle graph is a network containing a single cycle which passes through all its vertices.
Directed Graph: A directed graph is a network in which each edge is specified as going in a particular direction.
Planar Graph: A planar graph is a network that can be drawn in a plane without any edges intersecting.
Polyhedral Graph: A polyhedral graph is a network made up of the vertices and edges of a polyhedron. Polyhedral graphs are always planar.
Tree: A tree is a network that contains no cycles.


Function Graph: A function graph is a set of points showing the values taken by a function. This type of plot is called simply a "graph" in common parlance, but is distinct from a collection of points and lines (also called a network) that mathematicians refer to when they speak of a "graph."

Classroom Articles on Graph Theory

  • Chromatic Number
  • Graph Theory
  • Graph Cycle

  • Classroom Articles on Discrete Mathematics (Up to College Level)

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  • Magic Square
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