dot  ``hierarchical'' or layered drawings of directed graphs.
The layout algorithm
aims edges in the same direction (top to bottom, or left to right) and
then attempts to avoid edge crossings and reduce edge length.


neato  ``spring model'' layouts. Neato attempts to minimize
a global energy function,
which is equivalent to statistical multidimensional scaling.
The solution is achieved using stress majorization, though the older
KamadaKawai algorithm, using steepest descent, is also available.
fdp implements the FruchtermanReingold heuristic including a multigrid
solver that handles larger graphs and clustered undirected graphs.


fdp  ``spring model'' layouts similar to those of neato, but
does this by reducing forces rather than working with energy.
Fdp implements the FruchtermanReingold heuristic including a multigrid
solver that handles larger graphs and clustered undirected graphs.


sfdp  multiscale version of fdp for the layout of large graphs.


twopi  radial layouts, after Graham Wills 97. The nodes are placed on
concentric circles depending their distance from a given root node.


circo  circular layout, after Six and Tollis 99, Kauffman and Wiese 02.
This is suitable for certain diagrams of multiple cyclic structures such
as certain telecommunications networks.

