Call Waiting lets you put one call on hold to answer another. Don't feel like answering the other line? Don't worry, just let the call go to voicemail and respond at your convenience.
When a call comes in while you're on the other line, you'll hear a "beep" to notify you there is a phone call waiting. If you feel like answering the waiting call, press the flash button or switch hook. To return to your previous call, just press that flash button or switch hook again.
To turn off Call Waiting: