Cassiopeia A is the youngest core-collapse supernova remnant in the Galaxy, and one of the best studied supernova remnants overall. Imaging X-ray spectroscopy have a high information content, and show a clumpy structure of supernova ejecta, rich in oxygen, silicon and iron, with an uneven distribution across the remnant. The 4-6 keV band, however, is dominated by nonthermal X-ray emission, and the morphology shows thin (arcsecond-sized) filaments in two main regions: one associated with the supernova blast wave, and one with the reverse shock. In this talk I will detailed both the dynamics of the forward and reverse shock as measured using 20 years of observations with the Chandra X-ray Observatory, as well as measurements of the X-ray polarization with the recently launched Imaging X-ray Polarimetry Explorer (IXPE). The latter shows that the polarization degree is low. I will discuss how this could either be due to a high level of turbulence, or perhaps provides an hint for a "jitter radiation” component, jitter radiation being an extension of the synchrotron model, but in the presence of high turbulence at small physical scales.ry, as well as measurements of the X-ray polarization with the recently launched Imaging X-ray Polarimetry Explorer (IXPE). The latter shows that the polarization degree is low. I will discuss how this could either be due to a high level of turbulence, or perhaps provides an hint for a "jitter radiation” component, jitter radiation being an extension of the synchrotron model, but in the presence of high turbulence at small physical scales.