Windows Calc Bug

Know the windows calculator funny bug
Press Windows+R to prompt Run, type 'calc' (without single quotes), Windows calculator will open up in front of you. Now here's where we are going to have fun. I will enumerate the steps for clear understanding:
Step 1: Press 4(any integer whose square root is also an integer will do the trick)
Step 2: Press Square root button
Step 3: Press - (minus button)
Step 4: Press 2( for any other number, press its positive square root i.e don't press '-' button again, you will miss the fun)
Step 5: Press = (equal to button)

Now, you got to see some creepy number instead of our dear friend '0' (for Indians invented it).


Try it out with as many numbers as you wish, the answer will never be '0'