The program on the right contains a single statement, along with the comments. The statement declares a variable.

When you want to keep track of a value in a program you create a variable. In assembler we would have to decide which specific location in the memory of the PICmicro microcontroller which we wish to use, and then remember to refer to this location whenever we wanted to get hold of the value we have stored there.

In C, life is much easier. The compiler does all the hard work for us and will create different types of variable.

If you run the program you will find that when the declaration line is reached the variable count appears in the variable display area. The value in count at declaration is whatever number happens to be in memory at that location. In my case it seems to be 23. C does not clear the contents of variables for you, they must be set to explicit values before you use the number held by them.

/*  Simple Variable  */
void main ( void )
{
  /* create an integer variable  */
  int count ;
}