Square Inch (in²)
The square inch, or in², is the smallest commonly used unit of area in the imperial system. It is the area of a square with one-inch sides and equals 6.4516 square centimeters. It originates from the inch and has been widely used in engineering, technical drawings, and manufacturing. Today, it is still good for small things like screens, machine parts, and prints. Most countries now use square centimeters, but the square inch is still used in areas where the imperial system is prevalent.
Square Yard (yd²)
The square yard, or yd², is an area unit from the imperial system. It is the area of a square with one-yard sides and equals 9 square feet or 0.836127 square meters. Used first in England, the square yard was set as a standard in the 1900s. It is still used in the US and UK, particularly for real estate, carpets, fabrics, and sports fields. While most of the world now uses square meters, the square yard is still recognized and used in certain professions.