Since the mass usage of computers, direct numerical simulations or DNS have been used widely, producing vast data sets describing the complex evolution of flow. DNS indicates many complicated 3-dimensional vortices are embedded in regions of high shear near the surface. Researchers look around this region of high shear for indications of individual vortex structures based on accepted definitions, like coherent vortices. Historically, a vortex has been thought of as a region in the flow where a group of vortex lines come together hence indicating the presence of a vortex core, with groups of instantaneous circular paths about the core. In 1991, Robinson defined a vortex structure to be a core consisting of convected low pressure regions, where instantaneous streamlines can form circles or spiral shapes relative to the plane normal to the vortex core plane. Although it is not possible to track the evolution of hairpins over long periods, it is possible to identify and trace their evolution over short time periods. Some of the key notable features of hairpin vortices are how they interact with the background shear flow, other vortices, and how they interact with the flow near the surface.