  We discuss two main universal dynamic crossovers in a liquid that correspond
to relaxation times of 1 ps and 10^{-7}--10^{-6} s. We introduce the concept of
liquid elasticity length $d_{\rm el}$. At room temperature, $d_{\rm el}$ is
several \AA in water and increases to 0.01 mm in honey and 1 mm in tar. We
discuss that on temperature decrease, $d_{\rm el}=d_{\rm m}$ and $d_{\rm el}=L$
correspond to the two dynamic crossovers, where $d_{\rm m}$ is the medium-range
order and L is system size. The second crossover defines all kinetic aspects of
the glass transition whereas ``thermodynamic'' glass transition is realized in
the limit of infinite system size only. One prediction of this picture is the
increase of viscosity with the size of macroscopic system, which we verify by
measuring the viscosity of honey.
