diff --git a/cosmo.el b/cosmo.el
index a3d10ada66d6d5e771f23a7b369ec3766b8f25c0..d626f3dac9caaccc6d03346bf035f056bee56cd8 100644
--- a/cosmo.el
+++ b/cosmo.el
@@ -26,11 +26,26 @@
;;; Commentary:
-;; This package provides a cosmological calculator for Lambda-CDM
-;; models. Such a framework describes a homogeneous and isotropic
-;; universe containing a cosmological constant (Lambda) and a Cold
-;; Dark Matter (CDM) component, besides ordinary species. The
-;; model is characterized by the following parameters:
+;; Cosmological calculator for Lambda-CDM models.
+;;
+;; The package provides interactive commands for handy computation of
+;; cosmological distance measures. For instance, to display a summary
+;; table, type:
+;;
+;; M-x cosmo-calculator
+;;
+;; and to set cosmological parameters, type:
+;;
+;; M-x cosmo-set-params
+;;
+;; All cosmological quantities are computed at a given value for the
+;; gravitational `redshift' of photons frequency due to the expansion of
+;; the Universe.
+;;
+;; The Lambda-CDM model describes a homogeneous and isotropic universe
+;; containing a cosmological constant (Lambda) and a Cold Dark Matter
+;; (CDM) component, besides ordinary species. It is characterized by
+;; the following parameters:
;;
;; - H_0 :: Hubble parameter (expansion rate) today.
;; - Omega_m0 :: Matter density parameter today.
@@ -42,12 +57,6 @@
;; according to Friedmann's equation
;; Omega_m0 + Omega_Lambda + Omega_r0 + Omega_k0 = 1.
;;
-;; All cosmological quantities are computed at a given redshift
-;; value:
-;;
-;; - redshift :: Gravitational redshift of photons frequency due to the
-;; expansion of the Universe.
-;;
;; Definitions follow Hogg (1999)
;; .
;;