The importance of declaring a variable as unsigned

Question

Is it important to declare a variable as unsigned if you know it should never be negative? Does it help prevent anything other than negative numbers being fed into a function th

Answer 1

By using unsigned when signed values will not be needed, in addition to ensuring the datatype doesn't represent values below the desired lower bound, you increase the maximum upper bound. All the bit combinations that would otherwise be used to represent negative numbers, are used to represent a larger set of positive numbers.