You can either buy Xanax online or get the medicine offline, but buying or selling Xanax without a proper prescription from a doctor is not permitted. Authorities may hold you liable for some penalty if you do so. Being yellow-colored long rectangular tablets, Xanax is also known as yellow school bus bars. These school bus pills have the maximum potency and, therefore, the availability of Xanax yellow bars in the market is relatively less. You can easily order Xanax online from a legitimate online pharmacy store and use it as per your doctor's advice. However, it is always advisable to take care of all the necessary precautions while using Xanax. It is a highly addictive and habit-forming medicine; using it without asking your doctor can be dangerous. You should take Xanax according to your doctor only and tell them if you don't observe any improvement in your condition.