Square feet is a unit of area measurement commonly used in the United States and other countries that follow the imperial system. It represents the area of a square with each side measuring one foot in length. This measurement is often used in real estate to describe the size of homes, apartments, and commercial spaces. To calculate the area in square feet, you multiply the length by the width of a space. For example, a room that is 10 feet long and 12 feet wide has an area of 120 square feet. Understanding square feet helps individuals make informed decisions when buying or renting properties.