Convert Square Kilometer to Hectare

The square kilometer is derived from the kilometer, which is a unit of length in the metric system. The kilometer itself was introduced in the 18th century as part of the metric system, based on the meter, which was originally defined as one ten-millionth of the distance from the North Pole to the equator. The square kilometer, like other area units in the metric system, is based on the square of the unit of length. As the metric system became more widely adopted worldwide, the square kilometer became a standard unit for measuring large areas, particularly in geography, urban planning, and land management.

The hectare was introduced in the 18th century as part of the metric system and is derived from the meter, the base unit of length in the metric system. The word "hectare" comes from the Greek word "hekaton" meaning "hundred," combined with the metric unit "are" (which represents 100 square meters). The hectare was designed to provide a practical unit for measuring larger areas, such as farmland and forests, in a way that fits within the metric system. Today, the hectare is widely used across the world for land measurement, although it is not commonly used in the United States, where acres are preferred instead.