Thanks for writing. An interesting question that I bet a lot of people think about when they get a prescription.
Without knowing the medication you are taking or the condition that is being treated, it is difficult for me to be precise. However, it depends on how your doctor wrote the prescription. If she wrote to take your medication "qid," then that means 4 times a day spread over the waking hours. If she wanted you to take the medication every six hours, then she would have written "q6h."
Your pharmacist interprets these notations and provides the directions on the bottle. If you need a more exact answer, speak with your pharmacist; he knows how the medication should be used and what your doctor ordered.