“spring model” layouts.
neato is a reasonable default tool to use for undirected graphs that aren’t
too large (about 100 nodes), when you don’t know anything else about the graph.
neato attempts to minimize a global energy function, which is equivalent to
statistical multi-dimensional scaling.
The solution is achieved using stress majorization, though the older Kamada-Kawai algorithm1, using steepest descent, is also available.