A square foot (sq ft or ft²) is a unit of area commonly used in the United States and some other countries that use the imperial system of measurements. It is defined as the area of a square with sides that each measure one foot (12 inches) in length.
In terms of square meters, one square foot is approximately equal to 0.092903 square meters.
Square feet are frequently used to measure the area of rooms in houses, apartments, and other real estate properties. They are also used for various purposes in construction, architecture, and interior design.
A square chain is a unit of area measurement that is now considered obsolete and not commonly used. It was historically used in some English-speaking countries, including the United States and the United Kingdom, as part of the older system of land measurement.
One square chain is equal to an area of 10 square rods, or 484 square yards. In terms of square meters, one square chain is approximately equal to 404.68564224 square meters (m²).
The square chain was often used in land surveys and property descriptions in the past, but it has been largely replaced by the more standardized metric and imperial systems of measurement. In modern times, square meters and square feet are the more commonly used units for measuring land area.