The amount of time that passes from the instant network content is first produced, until it first appears at the destination point. Interactive voice content requires very low latency because humans easily perceive it. A good example of perceivable latency in a voice connection is when you are speaking on an international long distance call, or when you are speaking cell phone to cell phone. The latency is the amount of time that passes from the time the speaker utters a word until the time the hearer first begins to hear it.