The are is a unit of area and is a non-SI but metric unit with the symbol a.
It measures exactly 100m² which is the equivalent to 0.0247 acres.
The are is the principle unit for measuring the size of land across the world.
The square yard is a unit of area and is an imperial unit with the symbol ya².
One square yard is equal in area to a square with edges one yard in length. It also equals 1,296 in² and ≈ 0.836 m².
The square yard is a common unit of measurement in the UK and US.