2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/1075This lecture gives a short introduction to different methods used in cosmology. The focus is on major features of N-body simulations: equations, main numerical techniques, effects of resolution, and methods of halo identification.Lecture at the Summer School "Relativistic Cosmology: Theory and Observations", Italy, Como, May 2000. AASTeX and natbibAstrophysicstext