Printed circuit boards (PCBs) are essential components used in electronic devices to connect and support various electronic parts. They are made from a non-conductive material, typically fiberglass, with conductive pathways etched onto their surface. These pathways allow electricity to flow between components like resistors, capacitors, and integrated circuits, enabling the device to function properly. PCBs come in various shapes and sizes, depending on the specific application. They can be single-sided, double-sided, or multi-layered, accommodating complex circuits. Commonly found in devices such as smartphones, computers, and home appliances, PCBs play a crucial role in modern electronics.