If you think of the Internet as a series of tubes, Bandwidth is how wide the tube is. Indeed, it’s named bandwidth because it describes the width of the communications band. The wider the tube the more data you can send in parallel.
Latency is the length of the tube between two points. The key point here that gets missed is that, regardless of how much data you are sending (how much bandwith), you still have to move it the distance from point A to point B. That takes time and that is the latency.
Simply said, time difference in packet inter-arrival time to their destination can be called jitter. In this image above, you can notice that the time it takes for packets to be send is not the same as the period in which the will arrive at the receiver side. One of the packets encounters some delay on his way and it is received little later than it was assumed. Here are the jitter buffers entering the story. They will mitigate packet delay if required. VoIP packets in networks have very changeable packet inter-arrival intervals because they are usually smaller than normal data packets and are therefore more numerous with bigger chance to get some delay.