The wake dynamics behind a thin, normal flat-plate was analyzed using the direct numerical simulation technique at Reynolds number 400. The near wake flow becomes moderately turbulent, and low-frequency modulation of the near wake was observed. This modulation resulted in a high drag regime, where more coherent von-Karman (V-K) vortices were shed close to the plate, and a low drag regime where less coherent V-K vortices were shed away from the plate. Distinct flow structures were observed in these two drag regimes. POD analysis was carried out to identify the most dominant modes in the flow. The low frequency modulation of the wake was captured by the third dominant POD mode. The statistical analysis was also performed to study the variation of Reynolds stresses and fluctuating kinetic energy in the wake, and it qualitatively agrees with the numerical studies carried out previously for the same configuration.