A rotary hammer is a go-to drill if you are looking to drill large holes. The heavy-duty tool is used for chiseling and drilling through hard materials. Rotary hammers compress air using a piston and create the hammering action by moving the striker. The blows on a rotary hammer move at a slower rate compared to a hammer drill. This is because the force of impact on a rotary hammer drill is more powerful than a hammer drill. A stronger force will require less effort from the person handling the drill. Rotary hammers have a spring-loaded chuck that accommodates the exact size of the bits used. There is no adjustability. Only specific bits can fit the chuck of a rotary hammer. Rotary hammers are suitable for light demolition work. There is only a hammer mode available on a rotary hammer. A hammer drill uses a specialized clutch system that uses two rigged metal disks that work like gears. The disks spin against one another, causing the ridge to move up and down, which then allows the chuck to go in and out. This results in the drill bit rotating in an up and down movement. The hammering action is fast and not as deep as a rotary hammer. The bit only travels a small distance, delivering up to 30,000 blows per minute. A hammer drill has two modes of drilling that you can choose from, once you change bits, you can go from drilling in concrete to drilling in wood. Hammer drills are usually bulkier than your typical drill. They have a standoff handle to help you keep the tool steady. Rotary hammers are suitable to use on big projects such as drilling through rebar or breaking up concrete. The powerful force that a rotary hammer provides will cost more than a hammer drill. If you are not planning on doing any big projects and you just want a tool suitable for minor home tasks or light carpentry, a hammer drill is your best option.