# Planar graph

#### bogdan

What is the definition of a planar graph and which properties does it have ?

#### lethe

a planar graph is one which can be drawn in a plane with no self-intersections. i believe the simplest nonplanar graph is the inscribed pentagram.

#### bogdan

Well...I know that...
But isn't there an "abstract" definition which explains what a planar graph is without using the concept of "plan" ?
Only relations between the components of the graph...

#### lethe

there are some theorems about when a graph is planar or not. but you want to do what now? define a planar graph without using a plane?

#### bogdan

Aaa...those theorems sound interesting...that's what I need...
Where can I find them ?
(I want to define a plane using a planar graph )

#### rutwig

See the book of F. Harary. He gives a complete review starting from the famous theorem of Kuratowski. The booklet by O. Ore does also deal a bit with planarity of graphs.

#### bogdan

If only I could find those books...anyway...I fount something on the Internet...but it's so complicated...

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