Difference between squaring a negative number and multiplying 2 equal negative numbers?

Question

I've seen some strange behavior on 3 different calculators. Whenever I enter -2^2, I get a -4, and when I enter -2 * -2 I get a positive 4. Why does squaring a negative and multiplying it by itself give different results? Isn't it the same procedure executed differently, and hence should give the same result (multiplying the negative number by itself, which should output a positive?).

Answer 1

As user314 said: Your calculator interpreted $−2^2$ as $−(2^2)$ instead of $(−2)^2$.

Putting number 2 inside the brackets solved the issue.