Engineering

Electronics

Hands-on places to learn electronics by actually building things.

Textbooks

Lessons in Electric Circuits (Website) — Tony R. Kuphaldt’s free multi-volume electrical engineering textbook, reformatted and updated by All About Circuits: volumes on DC, AC, semiconductors, and digital circuits, running from static electricity and Ohm’s law through capacitors, inductors, and RC/L-R time constants.

Electronics 101 (Course) — Ray Dall’s free 75-lesson fundamentals course, written over several years as a series of emails and now the basis of two published books and the syllabus at a handful of schools. It starts from what matter is and the history of electricity, keeps the maths deliberately light, and links every technical term to a glossary entry.

SparkFun Learn (Website) — 900+ hands-on tutorials spanning Arduino, sensors, wireless, and robotics, from your first blinking LED to full projects, each tied to real hardware.
Basic Electronics Tutorials (Website) — a free, encyclopedic reference organized into 30+ categories, from Ohm’s law, resistors, and capacitors through op-amps, logic gates, and oscillators, each topic explained with worked examples.
Adafruit Learning System (Website) — 3,000+ maker tutorials from Adafruit covering CircuitPython, Arduino, Raspberry Pi, sensors, and LEDs, written for every skill level.

w2aew (Channel) — 400+ numbered bench videos on hobby electronics, test and measurement, and ham radio, on YouTube since 2007, from transistor amplifier design to tuning a duplexer with a handheld VNA. A fan-made index sorts every video by number and by topic.