With call waiting, you don't have to miss important calls while you are on the phone. A special tone lets you know someone is trying to get through to you. The caller simply hears a normal ring - not a busy signal. You can then place your current caller on temporary hold and answer the call without even hanging up! For example, if you are on the phone with a salesperson and the school nurse is trying to reach you, she can! All you have to do is click over. No access code required.