2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/41841These lectures given to graduate students in theoretical particle physics, provide an introduction to the ``inner workings'' of computer algebra systems. Computer algebra has become an indispensable tool for precision calculations in particle physics. A good knowledge of the basics of computer algebra systems allows one to exploit these systems more efficiently.56 pages, lectures given at the "Seminario Nazionale di Fisica Teorica", Parma, September 2002High Energy Physics - Phenomenologytext