Hacker News on 19 October 2019

• Music Theory for Musicians and Normal People
• Structure and Interpretation of Computer Programs (1996) [pdf]
• An electric crate motor you can drop into your car
• ML From Scratch, Part 1: Linear Regression
• Why Does Inflammation Seem to Underlie All Sickness?
• All plastic waste could be recycled into new plastic: researchers
• When Medical Debt Collectors Decide Who Gets Arrested
• The $68k Fish: The future of salmon in the Pacific Northwest
• Trains in Switzerland are not allowed to have 256 axles
• Pop_OS 19.10