A planar embedding, also called a "plane graph" (Harary 1994, p. 103; Harborth and Möller 1994), "planar drawing," or "plane drawing," of a planar graph is an embedding in which no two edges intersect (or overlap) and no two vertices coincide. Equivalently, a planar embedding is an embedding of a graph drawn in the plane such that edges intersect only at their endpoints.
A planar straight line embedding of a planar graph can be constructed in the Wolfram Language using the "PlanarEmbedding" option to GraphLayout or using PlanarGraph[g].
Precomputed planar embeddings of some graphs are available in the Wolfram Language as GraphData[g, "Graph", "Planar"].
In general, planar graphs may have multiple homeomorphically distinct planar embeddings on the sphere. Graphs with a single homeomorphically distinct planar embedding are called uniquely embeddable, among which are all polyhedral graphs. Uniquely embeddable graphs have a unique dual graph.
The numbers of embeddings on the sphere of 2-connected planar graphs with 
, 2, ... nodes are given by 0, 0, 1, 3, 10, 61, 564, 7593,
123874, ... (OEIS A034889). The first case
where this exceeds the number of nonisomorphic 2-connected planar graphs occurs for
, where a single 5-vertex planar graph
has two distinct planar embeddings on the sphere.
Planar embeddings can also be considered for planar disconnected graphs, but a number of difficulties
arise (B. McKay, pers. comm., Nov. 18, 2025). One of these is defining
what it means for two drawings to be equivalent. For graphs with multiple connected
components, one component can be drawn inside a face of another, and if there are
many components they can be in each others faces in an arbitrarily complex manner.
There is also the question the surface on which the embedding is made. In the case
of a connected graph, the surface is usually taken
as a sphere and the graph is just drawn on the plane for
convenience by cutting a hole in the sphere and opening
it up to a plane. However, when there are two components, the hole must always be
put in a place such that the resulting plane drawing has the components side by side.
However, the choice of which face of each component that is on the "outside"
now matters. For three or more components, the situation gets more complicated and
not all drawings are equivalent on the sphere to side-by-side
drawings. The special case of 
where 
is connected is somewhat simpler, with the location of the
being equivalent to marking one face
of 
as special and the number of inequivalent ways of doing this depending on the automorphisms
of 
(B. McKay, pers. comm., Nov. 18, 2025).
