When using a circular saw, several safety precautions should be followed: 

•Wear appropriate personal protective equipment, including safety glasses and hearing protection.

•Ensure the saw's blade guard is in place and functional.

•Keep your hands away from the blade's path and use a push stick when cutting small pieces.

•Secure your workpiece properly to prevent kickback.

•Maintain a stable stance and a good grip on the saw.

•Avoid distractions and maintain focus while operating the tool.

A rotary hammer drill is a power tool primarily used for drilling into tough materials like concrete, stone, or masonry. It combines the action of a regular drill with a hammering motion, allowing it to break through hard surfaces more effectively. It's commonly used in construction and renovation projects.

A cordless impact driver is a power tool designed for driving screws and fasteners more efficiently. It delivers high torque in quick bursts, which helps to drive screws with less effort and prevent cam-out (slippage). Unlike a regular cordless drill, an impact driver doesn't have a traditional chuck that holds the bit, but instead uses a hex collet that accepts hex-shanked bits.

A torque wrench is a tool designed to apply a specific amount of torque (rotational force) to a fastener, such as a nut or bolt. It typically has a handle and a mechanism that allows you to set a desired torque value. When you apply force to the handle, the wrench clicks or releases when the set torque is reached, ensuring that the fastener is tightened to the correct specifications.