Visual Introduction to the Fourier Transform

An Intuitive and Easy to Understand Visual Explanation of the Fourier Transform.

This video by 3Blue1Brown provides a really great introduction to the fourier transform in a phenomenal visual way that just makes sense for why it is the way it is, which is quite beneficial for any mathematical tool, as they tend to seem very abstract and confusing if you don't have a good understanding of them. This video does a good job of providing this understanding I feel.

Additionally, if you are interested in quantum mechanics, the fourier transform is related to the Heisenberg uncertainty principle and 3Blue1Brown also has a video on it that I would suggest.