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.
Acre (ac)
The acre, or ac, is a unit of area used in the imperial and US systems. It originated in medieval England and referred to the land a team of oxen could plow in a day. Today, one acre is 4,840 square yards or 4,046.856 square meters. Acres are still used in the US, Canada, and the UK for real estate, land sales, and farms. While the metric system is more common worldwide, the acre is still used because it is part of tradition and is easier to use in daily life.