Some compilers give an error message on forgotten type casting. From that it shows good typing style casting. So you also avoid clerical errors that can lead to the program crash in the worst case. With some types it is also necessary to perform type casting comma on others Types, however, do this automatically for the compiler.
In short:Type casting is used to prevent mistakes.
An example of such an error would be:
#include <stdio.h>
#include <stdlib.h>
int main ()
{
int * ptr = malloc (10*sizeof (int))+1;
free(ptr-1);
return 0;
}

By default, one tries to access the second element of the requested memory. However, this is not possible, since pointer calculation (+,-) does not work for a void pointer.
The improved example would be:
int * ptr = ((int *) malloc (10*sizeof (int)))+1;

Here, typecasting is done beforehand and this turns the void pointer into its int pointer and pointer calculation can be applied. Note: If instead of error "no output" is displayed on the sololearn C compiler try another compiler.