  Properties of dark matter halos are reviewed. Taken from different
publications, we present results on (1) the mass and velocity functions, (2)
density and velocity profiles, and (3) concentration of halos. In the range of
radii r=(0.005-1)rvir the density profile for a quiet isolated halo is very
accurately approximated by a fit suggested by Moore etal (1997):
rho=1/x^1.5(1+x^1.5), where x=r/rs and rs is a characteristic radius. The fit
suggested by Navarro et al (1995) rho= 1/x(1+x)^2, also gives a very
satisfactory approximation with relative errors of about 10% for radii not
smaller than 1% of the virial radius. The mass function of z=0 halos with mass
below 10^{13}Msun/h is approximated by a power law with slope alpha =-1.85. The
slope increases with the redshift. The velocity function of halos with Vmax<
500km/s is also a power law with the slope beta= -3.8-4. The power-law extends
to halos at least down to 10km/s. It is also valid for halos inside larger
virialized halos. The concentration of halos depends on mass (more massive
halos are less concentrated) and environment, with isolated halos being less
concentrated than halos of the same mass inside clusters. Halos have intrinsic
scatter of concentration: at 1sigma level halos with the same mass have
Delta(log{c_vir})=0.18 or, equivalently, DeltaVmax/Vmax =0.12. Velocity
anisotropy for both subhalos and the dark matter is approximated by beta(r)
=0.15+2x/[x^2+4], where x is radius in units of the virial radius.
