The advent of high-spatial-resolution scanning probe microscopes, such as the scanning tunneling microscope, has afforded a remarkable view of atomic- and molecular-scale surface dynamics. In particular, use of scanning tunneling microscopy (STM) for the detailed investigation of surface behavior has extended the boundaries associated with the measurement, comprehension, and ultimately application of nanoscale phenomena. The fundamental understanding of surface dynamics at the atomic and molecular scale influences catalyst customization and use, structural alloy compositions, microelectronic device fabrication, and molecule-based nanoelectronics.