(square centimeter), (square meter), (square kilometer).
These units are different, but they are related:

Understanding the relationship between these units is key, but there's no need to memorize it- we can quickly calculate it when needed.
Notice that in the metric system, each step in linear measurement is \(100× (1m = 100text{cm})\), so for area measurements, the conversion factor becomes .
Let's say we want to calculate how many are in . We’ll draw a square whose sides each measure meter:

To calculate the area of the square, we need to multiply the length of one side by the other (this is a well-known formula). In our case:
The area of the square .
The result is m² or, writing it another way:
Notice that area units are always "squared" (raised to the power of 2). This is because area measures two dimensions - length and width. When we multiply these two measurements together, we get: