ELI5: Explain Like I'm 5

Printed circuit board

A printed circuit board (PCB) is a special kind of board that is used to connect electronic components in a circuit. It looks like a green plastic board with lots of small lines going across it. The lines are made of copper and they create electric connections between all the other electronic components in the circuit, like the wires would in a wire-based circuit. This helps to make the circuit more efficient. PCBs are used in all kinds of electronics, like computers, phones, and toys.
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