What is jitter?
In one sentence: How much the waiting time wobbles from one message to the next; big wobbles make calls choppy and games jumpy.
A little more
Jitter is how much the waiting time (latency) wobbles from one message to the next. If one answer takes 20 milliseconds, the next 21 and the next 80, the connection has a lot of jitter, even if the average sounds fine.
Video calls and games hate jitter more than a steady delay, because sound and pictures have to play in order. Apps keep a small waiting area to smooth the bumps out, but big wobbles make voices go robotic and players jump around. Wi-Fi and a busy internet line are the usual causes.
It's a bit like… A school bus that is sometimes on time and sometimes twenty minutes late: a bus that is always five minutes late is easier to plan around.
See it in action
- 14How can lots of people play the same game together?Share a pretend park with friends in other houses: every move is a message to a shared world on a server.7 min · interactive
- BonusWhy does the video call freeze when you walk to the kitchen?A phone holds one Wi-Fi box's baton at a time, and the phone decides when to pass it on.7 min · interactive
- BonusWhy does the game lag when someone starts a download?Your internet line is a shop with one checkout and a download is a shopper with endless trolleys.9 min · interactive
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