what does malloc mean in c code example

Example 1: malloc in c

#include <stdlib.h>

void *malloc(size_t size);

void exemple(void)
{
  char *string;
  
  string = malloc(sizeof(char) * 5);
  if (string == NULL)
    return;
  string[0] = 'H';
  string[1] = 'e';
  string[2] = 'y';
  string[3] = '!';
  string[4] = '\0';
  printf("%s\n", string);
  free(string);
}

/// output : "Hey!"

Example 2: malloc c

int main(int argc, char *argv[])
{
    int* memoireAllouee = NULL;

    memoireAllouee = malloc(sizeof(int));
    if (memoireAllouee == NULL) // Si l'allocation a échoué
    {
        exit(0); // On arrête immédiatement le programme
    }

    // On peut continuer le programme normalement sinon

    return 0;
}