2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/211325Ultraperipheral collisions at collider energies are a useful tool to study photon-hadron (proton/nucleus) and photon-photon interactions in a hitherto unexplored energy regime. Theoretical tools to study these processes are briefly described. Some current results and problems are discussed5 pages, 2 figures. Talk given at the Workshop on 'High-energy photon collisions at the LHC', April 22-25,2008, CERN, Switzerland. To be published in Nucl. Phys. B (Proceedings Supplements)High Energy Physics - PhenomenologyHigh Energy Physics - Experimenttext