2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/9113A simple introduction to physics of CMBR polarization and the Faraday rotation of the latter in cosmic magnetic field is presented. The content of the lecture is the following: 1. Description of polarization of photons. 2. Polarization field of CMBR. 3. Faraday effect. 4. Cosmic magnetic fields. 5. Faraday rotation of CMBR polarization.15 pages, 3 figures; a lecture presented at Ecole Internationale d'Astrophysique Daniel Chalonge, WMAP AND THE EARLY UNIVERSE, 9-10 December 2004, Paris; one reference is addedAstrophysicstext