Which of the following is not a type of nail?

Lumber is not a recognized type of nail. In the context of fasteners used in construction and woodworking, nails are typically classified into specific categories based on their shape, size, and intended use. Common nails, wire nails, and finishing nails are all established categories that serve different purposes in construction and assembly.

Common nails are robust nails used for general construction, such as framing, while wire nails are made from wire and are generally thinner, often used for lighter materials. Finishing nails are designed for precise work and have small heads that can be easily concealed in the wood, making them suitable for trim and cabinetry.

Lumber, on the other hand, refers to wood that has been processed into beams, planks, or boards, and is not a type of nail. Thus, identifying lumber as the answer highlights an understanding of the distinction between types of fasteners and materials used in woodworking and construction.