The "smallest" type in the C language is the char type. You can use it to create variables with a size of no more than one byte.
#include <stdio.h>
#include <stdlib.h>
int main ()
{
char c = 7;
printf ("Our variable of type char is equal %d\n", c);
printf ("Size of char type variables is %lld bytes\n\n", sizeof (char));
return 0;
}