Order of operations - why are they in the order they're in? I understand the order of operations, but why are they ordered the way they're ordered? Is there a particular reason why multiplication should have a higher precedence than subtraction, other than to prevent ambiguity?
Edit: I'm a curious software developer that's relatively lousy at math. A simple explanation that your grandma could understand would be very welcome. :-)

I don't think there is any mathematical reason. The order of operations is only a matter of notation to save some brackets.
Careful: a typical calculator does not have a different order of operations but none at all instead. So 
5 - 4*3 on a calculator is actually (5-4)*3 while with our convention for algebra it is 5-(4*3).
Both assumptions are valid, the latter one is just the more common form.
