Circuit boards can be classified into three major categories based on the number of layers: single panel, double-sided board, and multi-layer circuit board.

  Firstly, on a basic PCB, the components are concentrated on one side, while the wires are concentrated on the other side. Because the wires only appear on one side, this type of PCB is called a single-sided circuit board. Single panel manufacturing is usually simple and cost-effective, but its disadvantage is that it cannot be applied to overly complex products.

  Double panel is an extension of single panel. When single-layer wiring cannot meet the needs of electronic products, double-sided panels need to be used. Both sides are covered with copper and have routing, and the wiring between the two layers can be conducted through vias to form the required network connection.

  Multilayer board refers to a printed circuit board with three or more layers of conductive patterns and insulating materials sandwiched between them, and the conductive patterns are interconnected as required. Multilayer circuit board is a product of the development of electronic information technology towards high speed, multifunctionality, large capacity, small size, thinning, and lightweight.

  If circuit boards are classified according to their characteristics, they can be divided into soft boards (FPC), hard boards (PCB), and soft hard junction boards (FPCB).