But what is a convolution?
As promised, here's a new video going deeper into convolutions, and in what sense the FFT algorithm can be used to speed up their computation. Originally the plan was to do an overview of both the discrete and continuous cases, but there was enough material I wanted to cover that I decided to pull out the continuous discussion into its own video. Given that many of the visuals for that are already made, in theory, it shouldn't be too long before that one is out as well. Let me know if there's anything you'd like to see for the continuous case.