Overview of quarkonia and heavy flavour measurements by CMS

This writeup summarizes recent CMS results on quarkonia measurements in pp, pPb and PbPb collisions at LHC. The excellent muon detection capability of CMS allows measurement of charmonia states at high transverse momentum ($p_T$) while the $\Upsilon$ states can be reconstructed starting at zero $p_T$. The absolute and relative yields of different charmonia and bottomonia states modified in PbPb collisions (over pp collisions) are described. The vertexing capability of CMS enables measurement of B meson energy loss via its decay to J/$\psi$. An overview of these measurements is given. How these measurements compare with other experiments at RHIC and LHC and have improved the understanding of heavy ion collisions has been discussed.