Term of the Day: Latency
 

In general, the period of time that one component in a system is spinning its wheels waiting for another component. Latency, therefore, is wasted time. For example, in accessing data on a disk, latency is defined as the time it takes to position the proper sector under the read/write head.

In networking, the amount of time it takes a packet to travel from source to destination. Together, latency and bandwidth define the speed and capacity of a network.

Re: Term of the Day: Latency
 

I believe that also, in networking, latency can refer to how long it takes a signal to make it through a router.  Obviously the latency would be extremely minimal, but could be a factor if you're buying a router for a really massive network, or something.  Feel free to correct me if I'm wrong.