Post a response in two parts. First, speak briefly about your biggest challenges in JavaScript programming, especially any concepts that you still don't fully understand. Use this portion of the Discussion to harness the collective knowledge of your classmates, your instructor, and their combined experiences. If you had no difficulty with the Application, identify potential problem areas you imagine other students may have faced but you were able to avoid, and explain how you were able to steer clear of those errors.

In the second part of the Discussion, challenge your classmates to debug a JavaScript program in which you have intentionally made exactly two different kinds of errors. For the sake of uniformity, everyone will construct a similar program, a JavaScript application that calculates the remainder when one whole number is divided by another whole number. Your post should contain all of the necessary code for this application. You may choose to replicate the errors you described in the first part of the discussion or introduce different errors.