A "microinch" is a unit of length used to measure extremely small distances or dimensions. It is equal to one millionth of an inch or 0.000001 inches. In scientific notation, it can be represented as 1 µin (pronounced as "one microinch").
Microinches are typically used in precision engineering, manufacturing, and industries where very fine tolerances and high levels of accuracy are required. This unit allows for the measurement of surface finishes, material thicknesses, and other minute details with extreme precision.
To put it into perspective, a microinch is much smaller than a human hair, which is typically several thousand micrometers (µm) or microns in diameter.
A "hand" is a unit of measurement commonly used in the context of measuring the height of horses. In the United States and some other English-speaking countries, a hand is defined as exactly 4 inches or 10.16 centimeters.
Horses are typically measured in hands from the ground to the highest point of their withers (the ridge between the shoulder blades). This measurement is a convenient way to describe a horse's height without relying on feet and inches or meters.
For example, a horse that measures 15.2 hands is 15 hands and 2 inches tall. Horses can vary in height, and the hand system provides a standardized way to communicate a horse's size, which is particularly important in horse racing, equestrian sports, and the horse industry in general.