FR-4, is a widely acceptable international grade desination for fiberglass reinforced epoxy laminated that are flame retardant (self extinguishing). After add copper layer on one or each side FR4, it become to Copper Clad Laminate (CCL), and this is the non-conductive core materail for normal printed cricuit board (PCB). Printed circuit board using FR4 as core material will be named as "FR4 PCB".

PCB is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper clad laminate substrate. Sometimes, PCB also named Printed Wiring Board (PWB) or etching wiring board if no extra electronic components was added on.

A single-sided PCB has only one layer of conductive copper. Electronic components are mounted on this one layer. It is the simplest and cheapest type of PCB, commonly used in simple electronic devices like calculators and sensors.

A double-sided PCB has two layers of conductive copper, with components mounted on both sides of the board. Electrical connections between the layers are made through vias (plated-through holes). This type is suitable for moderately complex circuits such as industrial controls and power supplies.

Multi-Layer PCBs consist of three or more layers of conductive copper separated by insulating layers. The layers are interconnected by blind vias, buried vias, and through vias. These PCBs are used in complex electronic devices like computer motherboards and communication equipment, providing higher circuit density and functionality.

Rigid-flex circuits combine the features of both rigid and flexible PCBs. Parts of the board are rigid, while other parts are flexible, allowing the board to bend and fold during installation. This design is used in applications requiring high-density assembly and 3D configurations, such as mobile devices and aerospace electronics.

Heavy copper PCBs use thicker copper layers (typically over 3 oz/ft²), providing higher current carrying capacity and better heat dissipation. They are commonly used in high-power electronics, power converters, and automotive electronics.

HDI PCBs have higher wiring density, finer lines and spaces, and smaller vias. They use laser drilling technology and feature microvias, blind vias, and buried vias. These PCBs are used in high-performance computing, smartphones, and other advanced electronic devices, offering higher performance and smaller sizes.

High Tg PCBs use materials with a higher glass transition temperature (Tg), maintaining stable mechanical and electrical properties at elevated temperatures. They are suitable for applications in high-temperature environments such as automotive electronics and industrial equipment.

Extra thin PCBs typically have a thickness of less than 0.8 mm, making them suitable for applications with space constraints. These PCBs are common in consumer electronics such as smart cards and wearable devices due to their lightweight and flexibility.

RF boards are designed for high-frequency signal transmission and use materials with low loss and high dielectric constant to ensure signal integrity and stability. They are widely used in wireless communication devices, satellites, and radar systems.