Core drill bits are designed to remove a cylinder of material, the left material left inside is referred to as the core. Core drills are used in many applications where the core needs to be retained or where the drilling can be done more rapidly since much less material needs to be removed compared to using a standard drill bit.
There a few types of core drill bits for different types of materials:
Diamond Core Drills: This core drill is used for concrete are generally Diamond core drill bits and are water cooled. Diamond tipped core drills are commonly used in construction to create holes for pipes and inspection hatches.
Carbide Core Drills: This works great on masonry tasks, but it is not intended for solid concrete. This prolonged deep drilling will easily overheat the bit to the point it will significantly decrease wear life.
Annular Core Drills: These drills are used for drilling metal.