1. Plywood is divided into two departments: three-layer or multi-layer veneer bonding. The vast majority of veneer produced nowadays is spun veneer, often referred to as veneer. Odd layer veneer is usually used, and the fiber directions of adjacent layers of veneer are perpendicular to each other. It is common to see odd layer plywood such as three, five, and seven layers. The outermost layer of veneer is called surface board, the front surface board is called panel, the back surface board is called back board, and the inner layer of veneer is called core board or middle board.