Question

What are the advantages and disadvantages of using a rod of a given length as a unit of length?

Answer 1

Since in English measurements (Great Britain and US at least) a “rod” is actually a defined length of 16.5 feet, which is 1/320 of a mile. Advantages of using some given rod as a unit of length is that you can measure anything against it. However, a disadvantage is that, unless you have way to subdivide its length, you will have problem with measuring anything which is not an even multiple of the length of the rod.