What's difference between idenfiers and variables in C?

Question

Please answer with examples.

Answer 1

An identifier is the "name" of a variable.

int d;

d is the identifier to a 16/32-bit section of memory that is to be interpreted as an integer.

int x = 5;
printf("%d\n", x); //prints 5
int *p = &x; //a pointer to the location of x.
*p = 7;
printf("%d\n", x); //prints 7

As you can see in the example above, you can change the memory that sits at the location of x without using the "x" identifier.

Answer 2

a variable is an identifier, but an identifier can be something else, like a function or a macro for example