A router plane is a woodworking tool used for creating flat, smooth surfaces on wood. It features a flat base and a cutting blade that can be adjusted to different depths, allowing for precise control when shaping or trimming wood. This tool is particularly useful for hollowing out areas, such as grooves or dados, and is often employed in fine woodworking projects. The router plane is typically used in conjunction with other tools, such as chisels and hand planes, to achieve a high level of detail. It is especially favored by woodworkers for its ability to work on end grain and for its versatility in various woodworking tasks, making it an essential tool in the woodworking toolkit.