This Topic considers the concept of aliasing, which is signal distortion due to the spectral overlap of the spectral images that result from the sampling process. This Topic discusses the condition under which aliasing occurs, and investigates what happens when the spectral images are summed together, and the resulting signal after the reconstruction filter. The Topic then considers strategies for how to avoid aliasing in practice, including the notion of anti-aliasing filters, and oversampling. The video also considers the limitations of practical data systems, such as imperfect low-pass filters in the anti-aliasing and reconstruction filters, as well as imperfect sample-and-hold and DACs. Finally, the video considers the exemplar case of high-resolution audio.