what does a busy signal mean on a cell phone
Many people are familiar with the sound, as it differs markedly from the dial tone, the tone that indicates that the phone line is open and ready to be dialed. In most cases, a busy signal simply indicates that the person being called is on the phone, or that the phone is off the hook. In these instances, the signal indicates that there is no technical obstacle to placing the call, but that the call cannot be completed because the phone is in use.