Using lasers to induce and probe surface processes has the advantages of quantum state specificity, species selectivity, surface sensitivity, fast time-resolution, high frequency resolution and accessibility to full pressure ranges. These advantages make it highly desirable to use light to induce, control or monitor surface chemical and physical processes. Recent applications of laser based techniques in studying surface processes have stimulated new developments and enabled the understanding of fundamental problems in energy transfer and reactions. This text, along with volume 2, includes discussions on spectroscopic techniques, energy transfer, desorption dynamics and photochemistry.