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.
Square Meter (m²)
The square meter, or m², is the basic unit of area in the metric system. It is the area of a square with sides one meter long. First used in France in the late 1700s, it helped make measurements simpler and the same everywhere. Today, the square meter is the primary unit of measurement for areas, including rooms, buildings, and land. Its accuracy and clear links to other metric units make it a key unit in building, real estate, design, and science.