A brad nailer is a type of power tool used for fastening thin pieces of wood or trim. It uses small, thin nails called brads that are typically 18-gauge, making them less likely to split the wood. Brad nailers are commonly used in woodworking, cabinetry, and home improvement projects for tasks like attaching moldings or securing lightweight materials. These tools can be powered by electricity, batteries, or compressed air, offering versatility for different work environments. A brad nailer is favored for its ability to create a clean finish, as the small nails leave minimal visible holes, which can be easily filled or painted over.