The nature of diffusion of lipids in a bilayer membrane plays a key role in various biological processes like cell signaling, cellular transport etc. Dioctadecyldimethylammonium bromide (DODAB) is a synthetic lipid that self-assembles to form bilayer. Here we describe the dynamical landscape of the DODAB bilayer in fluid phase using molecular dynamics (MD) simulation and quasielastic neutron scattering (QENS) techniques. MSD of lateral motion of the lipids calculated from MD simulations show subdiffusive behaviour. A model free approach is employed to describe the dynamics of lipids in the bilayer where the relaxation rates are distributed over a wide range. A stretched exponential relaxation function used to describe the incoherent intermediate scattering function of the lipids obtained from MD simulation and QENS experiments. The distribution of relaxation rates covers over three decades. The results of the MD simulation and QENS experiments agree well.