1N400x general-purpose diodes

A diode is a type of electronics component, and a 1n400x diode is a type of diode that is very good at allowing electricity to flow in one direction but preventing it from flowing in the other direction. Think of it like an automatic door that only swings one way - it lets people go through it in the direction it's expected, but it doesn't let people come back in the other direction. That's what a 1n400x diode does - it lets electricity flow in one direction but not in the other. It's mostly used in everyday electronics like TVs, radios, and computers.