A laser level is a tool used in construction and surveying to project a straight line of light across a surface. It helps ensure that structures are level and aligned accurately. By emitting a laser beam, it provides a visual reference point, making it easier to measure and mark straight lines for tasks like hanging shelves or installing tiles. There are different types of laser levels, including line laser levels, which project a straight line, and rotary laser levels, which can create a 360-degree horizontal or vertical plane. These tools are essential for achieving precision in various building and renovation projects.