A "nail" is a traditional unit of length used for measuring cloth or fabric, particularly in some regions of India. The nail is based on the width of a finger, and it is typically equal to approximately 2.25 inches or about 5.715 centimeters.
Nails were historically used in the textile and clothing industry to measure the width of cloth or fabric. However, like many other traditional units of measurement for textiles, the nail has largely been replaced by more standardized and metric units, such as inches, centimeters, or meters, in modern times.
A fathom is a unit of length used to measure the depth of water or the depth of objects underwater. In the international nautical mile system, one fathom is equal to exactly 1.8288 meters or approximately 6 feet. However, in the United States, the customary value for a fathom is often rounded to 6 feet.
Fathoms are commonly used in navigation, maritime activities, and underwater exploration to measure the depth of bodies of water, the draft of ships, and the depth of diving. Sailors, fishermen, and divers often use this unit to assess water depths.