1. **State the problem:** We want to calculate the area of a square. 2. **Formula:** The area $A$ of a square is given by the formula: $$A = s^2$$ where $s$ is the length of one side of the square. 3. **Explanation:** Since all sides of a square are equal, you only need to know the length of one side. 4. **Example:** If the side length $s = 4$, then the area is: $$A = 4^2 = 16$$ 5. **Summary:** To find the area of a square, simply square the length of one side.