* Cubit: The cubit was one of the earliest units of measurement, and it was based on the length of a man's forearm from the elbow to the tip of the middle finger.
* Hand: The hand was another early unit of measurement, and it was equal to the width of a man's hand.
* Foot: The foot was also an early unit of measurement, and it was equal to the length of a man's foot.
* Pace: The pace was another early unit of measurement, and it was equal to the distance that a man could walk in two steps.
* Fathom: The fathom was an early unit of measurement, and it was equal to the distance between the outstretched arms of a man.
Modern Times
* Meter: The meter is the modern unit of length, and it is defined as the distance traveled by light in a vacuum in 1/299,792,458 of a second.
* Kilometer: The kilometer is a unit of length that is equal to 1,000 meters.
* Centimeter: The centimeter is a unit of length that is equal to 1/100 of a meter.
* Millimeter: The millimeter is a unit of length that is equal to 1/1,000 of a meter.
* Micrometer: The micrometer is a unit of length that is equal to 1/1,000,000 of a meter.
The development of more accurate and precise units of measurement has been essential to the advancement of science and technology.