More than 25 years ago, Prof. Ned Seeman founded the field of Structural DNA Nanotechnology.  This area of nanotechnology uses the information inherent in DNA for structural purposes and to design functional components of self-assembled systems.  Branched DNA molecules that can be designed to self-assemble from synthetic strands are central to this effort.  Cohesive ends allow them to assemble to produce polyhedra and nanotubes.  In addition, DNA motifs have been used to produce 2D lattices that are characterized by atomic force microscopy.  3D lattices built the same way are studied by x-ray crystallography.  The goal is to use DNA to scaffold other species, such as biological macromolecules and nanoelectronic components.  This program has led to a variety of nanomechanical devices, including a translator, walkers and nanorobots.  Other research involves DNA-based computation and self-replicating systems.