# What is *area*?

**Area**is the space occupied by a flat shape or the surface of an object. The area of a shape can be measured by comparing the shape to squares of a fixed size. In the International System of Units (SI), the standard unit of area is the square meter, which is the area of a square whose sides are one meter long.

## Input

**Acre**is a unit of land area used in the imperial and US customary systems that is exactly equal to 4840 square yards or 1/640 of a square mile.

## Output

**Square Meter**is the SI-derived unit of area. It is defined as the area of a square whose sides measure exactly one meter.