An "are" (symbol: a) is a unit of area that is not part of the International System of Units (SI) but is used in some countries, particularly in Europe, for measuring land areas. One are is equal to 100 square meters (m²).
To put it simply, 1 are is equivalent to a square with sides that each measure 10 meters. It is a relatively convenient unit for measuring smaller land areas, such as gardens, small fields, or land plots, where using square meters might result in large numbers.
Here are some additional conversions to provide context:
For example, if you have a piece of land that is 5 ares in size, it would be equivalent to 500 square meters (5 ares * 100 m²/are = 500 m²).
A square mile (often abbreviated as sq mi or mi²) is a unit of area used primarily in the United States and a few other countries. It is defined as the area of a square with sides that each measure one mile in length. One square mile is equal to 640 acres.
In terms of the International System of Units (SI), one square mile is approximately equal to 2.58999 square kilometers (km²).
To provide some perspective, a square mile is commonly used to describe land areas within cities, counties, and states in the United States. It's a convenient unit for measuring larger land areas, such as the size of cities or counties.