Sometimes we need to make an electrical connection to the earth. A ground rod is the most common item used to make this "ground" connection. Driven into the soil, the ground rod is in firm contact with the soil. Ground rods are typically about 5/8 inch diameter and 8 feet long, but other diameters and lengths are also used. A connection is then made to the top of the ground rod. The connection can be a mechanical connection (clamp), or a welded or brazed connection. Wire is the most common conductor attached to the top of a ground rod, but braid or strap can be used as well, each with its own advantages and disadvantages.