Editing Packing problems (section)

===Hexagonal packing of circles===
[[File:Circle packing (hexagonal).svg|thumb|right|The hexagonal packing of circles on a 2-dimensional Euclidean plane.]]
These problems are mathematically distinct from the ideas in the [[circle packing theorem]]. The related [[circle packing]] problem deals with packing [[circle]]s, possibly of different sizes, on a surface, for instance the [[plane (geometry)|plane]] or a [[sphere]].

The [[N-sphere|counterparts of a circle]] in other dimensions can never be packed with complete efficiency in [[dimension]]s larger than one (in a one-dimensional universe, the circle analogue is just two points). That is, there will always be unused space if people are only packing circles. The most efficient way of packing circles, [[Circle packing|hexagonal packing]], produces approximately 91% efficiency.<ref>{{Cite web | url=http://mathworld.wolfram.com/CirclePacking.html |title = Circle Packing}}</ref>