A "Slicer" is a software tool used primarily in 3D printing and computer-aided design (CAD). It converts 3D models into instructions that a 3D printer can understand, typically in the form of G-code. This process involves breaking down the model into layers and determining how each layer will be printed, including the path the printer's nozzle will take. Slicers often come with various settings that allow users to customize print quality, speed, and material usage. Popular slicers include Cura, PrusaSlicer, and Simplify3D. These tools are essential for anyone looking to create accurate and detailed 3D printed objects.