The real difference between “int” and “unsigned int”

Question

int:

The 32-bit int data type can hold integer values in the range of −2,147,483,648 to 2,147,483,647. You may also refer to this data type as sig

Answer 1

He is asking about the real difference. When you are talking about undefined behavior you are on the level of guarantee provided by language specification - it's far from reality. To understand the real difference please check this snippet (of course this is UB but it's perfectly defined on your favorite compiler):

#include 

int main()
{
    int i1 = ~0;
    int i2 = i1 >> 1;
    unsigned u1 = ~0;
    unsigned u2 = u1 >> 1;
    printf("int         : %X -> %X\n", i1, i2);
    printf("unsigned int: %X -> %X\n", u1, u2);
}