A conventional reflection seismic record section displays data only as passing wavefield recorded at points on the earth's surface. In regions of complex geology, this display may bear little resemblance to a cross‐section of subsurface reflectors. Migration is the technique used to transform such a wavefield into a reflectivity display. Different migration methods are derived from either an integral or differential form of the scalar wave equation. In particular, a matched filtering technique involving summation of amplitudes along diffraction hyperbolas is founded on the integral form, and a finite‐difference method pioneered by Jon Claerbout, Stanford University, approximates direct solution of the differential form. After discussing fundamental assumptions required for implementation of the two migration approaches, this paper focuses primarily on comparison migrations of both synthetic data and of marine and land profiles. For good data of modest spatial dip, the two approaches produce similar results. However, the seismic trace spacing (receiver group interval) is found to play different, but fundamental, roles in governing the accuracy and signal‐to‐noise quality of both types of migration.