A rood is an old and largely obsolete unit of land area measurement. It was historically used in some English-speaking countries, particularly in the United Kingdom and Ireland, but it is not commonly used today, and its use in official measurements has been largely phased out.
In the traditional system, one rood is equal to one-quarter of an acre. This means that there are 4 roods in one acre. Converting to modern units, one rood is approximately 1,011.71 square meters (m²) or 0.101171 hectares (ha).
The term "rood" is often associated with medieval land measurement systems and was used in land and property transactions in the past. While it may occasionally appear in historical documents or literature, it is no longer a standard unit of measurement for land area in most countries.
A square kilometer (often abbreviated as km²) is a unit of area in the International System of Units (SI). It represents a square with sides that each measure 1 kilometer in length.
One square kilometer is equal to 1,000,000 square meters (m²) because there are 1,000 meters in a kilometer, and when you square that length, you get 1,000 * 1,000 = 1,000,000 square meters.
To visualize the size of a square kilometer, you can imagine a square plot of land, each side of which measures 1 kilometer (approximately 0.621 miles). It's a commonly used unit to measure land area, particularly in countries that use the metric system.