A magnetic drill, mag drill for short, is a drill used to cut metal. You can use a wide variety of tooling with mag drills including annular cutters, twist drills, taps, reamers, and counter sinks.
Magnetic drills have strong electromagnetic base enabling it to adhere to a carbon steel (ferrous metal) surface while turned on. Magnetic drills can be positioned to drill horizontally, vertically or overhead which is especially useful in construction. Be sure to secure your mag drill to the surface being drilled into, especially when overhead, to avoid drops.