Hectare (ha)
The hectare, or ha, is a metric area unit equal to 10,000 square meters (a square with 100-meter sides). First used in France in 1795, it is now widely used worldwide, particularly in farming, forestry, and land planning. Although it is not an official SI unit, it is permitted because it is practical for measuring fields and properties. Its simple size makes it better than the square kilometer for medium areas.
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.