Resampling (sample-rate conversion) is the DSP process of computing what a signal sampled at one rate would look like at another — 44.1 kHz to 48 kHz for delivery, or microscopic ratio adjustments to cancel clock drift in real time. It works by reconstructing the band-limited waveform and re-sampling it on the new grid, so the maths is essentially interpolation with a carefully designed filter. Quality is everything: a cheap converter introduces aliasing, passband ripple, or audible artefacts, while a good one is transparent. Resampling is everywhere audio crosses a rate boundary — between 44.1 and 48 kHz worlds, inside adaptive jitter buffers, and whenever a device's clock must be matched to the network.
