We present a self-contained summary of the theory of linear cosmological
perturbations. We emphasize the effect of the six parameters of the minimal
cosmological model, first, on the spectrum of Cosmic Microwave Background
temperature anisotropies, and second, on the linear matter power spectrum. We
briefly review at the end the possible impact of a few non-minimal dark matter
and dark energy models.Comment: TASI 2013 lecture note