The debugger statement can be placed anywhere in procedures to suspend execution. Using the debugger statement is similar to setting a breakpoint in the code. By definition such statement must absolutely be removed from the source code to prevent any unexpected behavior in production.

Here is an example of JavaScript code :

for (i = 1; i<5; i++) {
  // Print i to the Output window.
  Debug.write("loop index is " + i);
  // Wait for user to resume.
  debugger;
}