There are many types of printed circuit boards, which can be divided into different types according to different classification standards. According to different numbers of layers, they can be divided into single-layer boards, double-layer boards, multi-layer boards, etc.; according to different materials, they can be divided into FR-4, CEM-3, metal substrates, ceramic substrates, etc.; according to different uses, they can be divided into rigid boards, flexible boards, rigid-flexible boards, and soft-hard compatible boards, etc.
