That's true, but it's kind of the same idea, so it's okay. The best way to understand this, for people who are familiar with linear algebra, is to think of the

That's true, but it's kind of the same idea, so it's okay. The best way to understand this, for people who are familiar with linear algebra, is to think of the Fourier transformations as change-of-basis operations that convert signals from a time basis to a frequency basis. Depending for the bases for the time domain and the frequency domain, you get the Fourier series, Fourier transform, or Discrete Fourier transform[1]. I find the Fourier series is the hardest to understand intuitively (compared to FT and DFT), since the time basis (periodic functions of time) and the frequency basis (infinite sequence of Fourier coefficients) look very different. [1] https://minireference.com/static/excerpts/noBSguide2LA_preview.pdf#page=114 https://minireference.com/static/excerpts/noBSguide2LA_previ...