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.
Square Kilometer (km²)
The square kilometer, or km², is equal to one million square meters. It was designed for measuring large areas when the metric system was introduced. Square kilometers are often used in geography, maps, and environmental studies to represent the size of places such as cities, forests, and countries. For example, a country’s size is typically measured in square kilometers (km²). Its ease of use and simple conversions make it important for sharing global information.