The square centimeter (cm²) is a metric area unit equal to one ten-thousandth of a square meter, commonly used in medical reports, lab measurements, and small product specifications. Skin lesion sizes, fabric swatches, and circuit board components are often measured in square centimeters. One square centimeter equals exactly 0.155 square inches.

The mu (亩) is a traditional Chinese unit of area equal to approximately 666.67 square meters, used extensively in Chinese agriculture, rural land contracts, and property records. Farmland in China is almost always measured in mu, and government policies regarding grain production quotas reference this unit. One mu equals roughly 0.1647 acres or about 7,176 square feet.