Square Mile (mi²)
The square mile, or mi², is the area of a square one mile on each side, or 640 acres. Its history dates back to the mile, which originated in Roman times. The square mile became a set measurement in England. It is still widely used in the US and the UK for large areas, such as cities, counties, and parks. Most countries use square kilometers, but in English-speaking regions, the square mile remains common, especially in historical and legal contexts.
Square Foot (ft²)
The square foot (ft²) is a standard unit of area in both the imperial and US customary measurement systems. Defined as the area of a square with each side measuring one foot, one square foot equals 144 square inches or roughly 0.0929 square meters. Its origins date back to the Middle Ages, and it eventually became a fixed standard. Today, the square foot remains a popular unit in the United States, Canada, and the United Kingdom, especially for describing the size of residential and commercial spaces. Although metric measurements are more widely adopted worldwide, the square foot continues to be important in real estate and construction practices within these countries.