1. The problem is to find the result of the expression $7 - 12$. 2. The operation involved is subtraction, where we subtract 12 from 7. 3. Subtraction rule: When subtracting a larger number from a smaller number, the result is negative. 4. Calculate $7 - 12$: $$7 - 12 = -5$$ 5. Therefore, the final answer is $-5$.