1. The problem is to calculate $2 - 2$. 2. The subtraction operation means taking away the second number from the first. 3. Using the formula for subtraction: $$a - b = c$$ where $a=2$ and $b=2$. 4. Substitute the values: $$2 - 2 = c$$. 5. Calculate the result: $$2 - 2 = 0$$. 6. Therefore, the answer is $0$.