Signal Processing and Electronics

Electronics Theory
geofex.com - Impedance : What is it and why does it do all those terrible things to you?
Electronic Components
The Electronic-Hydraulic Analogy : Fluid mechanics and hydraulic circuits to build intuition for electronics
Guitar Pedals
Lab Notes: The Bazz Fuss Pedal : Notes on my understanding of the Bazz Fuss circuit
Transform Algorithms
3b1b - But what is the Fourier Transform? A visual introduction. : The first video I'd recommend anyone watch on the Fourier Transform
Seeing Circles, Sines, and Signals - The Fourier Transform? : Excellent explanation packaged in a masterclass of pedagogical visual design
weitz.de - The Discrete Cosine Transform : Real-valued relative of the Fourier transform, used in JPEG compression
yt/reducible - The Unreasonable Effectiveness of JPEG: A Signal Processing Approach : Great youtube video by Reducible on images as signals and JPEG compression

Spray Paint

artprimo.com - Caps 101 : An introduction to spray nozzles: the aerosol equivalent to different paint brushes

Color Theory

Colorspaces
makingsoftware.com - What is a Color Space? : Chapter on color spaces from an excellent book (with absolutely stunning design)

Languages

Korean
Korean Handwriting : Textbook fonts aren't how people actually write Korean