Nanometer (nm): The nanometer is equal to one one-billionth of a meter (0.000000001 meters). It is used to measure extremely small structures, such as molecules and nanoparticles.
In the United States surveying system, a "link" is a unit of length that is equal to 1/100th of a chain. Each link is approximately 7.92 inches long or about 0.201168 meters. This unit is primarily used in surveying and land measurement in the United States.
Surveyors often use a chain, which is comprised of 100 links, to measure distances in land surveys. The use of links and chains allows for precise measurements of land parcels, boundaries, and property lines.