  An extension of the Standard Model by three right-handed neutrinos with
masses smaller than the electroweak scale (the $\nu$MSM) can explain
simultaneously dark matter and baryon asymmetry of the Universe, being
consistent with the data on neutrino oscillations. A dark matter candidate in
this theory is the sterile neutrino with the mass in keV range. We discuss the
constraints on the properties of this particle and mechanisms of their
cosmological production. Baryon asymmetry generation in this model is reviewed.
Crucial experiments that can confirm or rule out the $\nu$MSM are briefly
discussed.
