have ever see a modern city from upper? Where buildings appear, and industrial units are arranged in a harmonious manner, and every building has an important role in that city, and all buildings are connected to each other by roads and railways, where it is possible to move from one place to another place freely, it is quite similar to an electronic circuit board inside an electronic device. So what is electronic circuit board, and what is it role?
Electronic circuit board:

Electronic circuit board: Is a board that found in every electronic device. Where The electronic components appear arranged and connected to each other, allowing the transfer of electrical charges from one component to another according to specific directions, according to the role of each component in this electrical circuit. Which makes an integrated electrical device, and capable of performing tasks for which it was made.
This board called: Printed Circuit Board (PCB), used to soldering electronic components and connect them together forming a circuit, using copper tracks instead of wires.
Types of PCBs:

- Single-Sided PCBs
- Double-Sided PCBs
- Multi-Layer PCBs
- Rigid PCBs
- Flex Circuits
- Rigid-Flex-PCBs
- High-Frequency PCBs
- Aluminum backed PCBs
The role of electronic circuit board:
The circuit board is used to perform a variety of tasks depending on the purpose for which it was designed. It is used in computers and electronic devices, where no electronic device is devoid of one or more main circuit boards.

The circuit board is mainly used to integrate the components of an electronic device into a compact space, in a way that allows the components to communicate with each other, as well as to extend them with power, without the need for a large number of electrical wires, thus forming an integrated circuit.
The most important components on a electronic circuit board include:

- Transistor
- Resistor
- Capacitor
- Diode
- Diode zener
- LED (Light Emitting Diode)
- IC (Integrated Circuit)
- Inductor
- Switch
- Battery
- microcontroller
- relay
With technological progress, it has become easy to design electronic boards that are small in size and with greater efficiency, and they are used in most electronic devices such as computers, smart phones, smart watches, TVs, robots, and other devices, containing only small consistent electronic boards without the need for huge wires, and large components. Therefore, most devices have become small in size and highly efficient.