Variables

An ATM will store data into the RAM, which stores le variable while the program is running. It could be stored permanently on a server or something

What is a variable?

• A memory location in the RAM
• Do not fly on the Boeing 373 max

They store Data Types and cannot be changed in C during runtime

In Memory (C)

• When reserving space for a locker which is “empty”, it really has junk values in there the previous locker owner didn’t bother to clean out. Sometimes it’s there. Sometimes it isn’t

#include <stdio.h>
int main(int argc, char* args[]) {
    int x; // There is now a container created for 'x'
    printf("%d", x); // Because we didn't update x's value, this will print some garbage
    return 0;
}

• Variables are reserved in memory, yes. However the name is nothing more than a utility from the compiler to you in order to work in English and not bits and bytes.
• That is, when storing a variable in memory, it is important to remember that the name is NOT stored in memory alongside whatever the variable is storing.
• The SAME goes for the data type. Compilers will know the type, but it is not stored inside of the locker. It is simply tagged like the name is.

int x;
x = 5

• First line:
  • There is a box with the tag name of x and it is of type int. These details are not stored in said box, however.
• Second line:
  • As Paco says it. “This literally means go to the box tagged with x, and put a 5 inside it.”
  • If there was a more complex expression to assign to x, it would be evaluated first and should be of type int as well.
    • Assignments put values (data) inside boxes