Wirebook › Glossary › Video buffer
What is a video buffer (and why does video buffer)?
In one sentence: Video a player has already downloaded but not shown yet, kept in hand so the picture keeps going when the connection wobbles.
A little more
A video buffer is the stretch of video a player has downloaded ahead of what you're watching. Film apps often keep tens of seconds to a few minutes in hand. While the connection is faster than the video needs, the buffer grows; when it slows, the video keeps playing from the buffer.
“Buffering” with a spinning circle means the buffer ran empty and the player is waiting for more. Skipping ahead empties it, which is why a video can pause or go blurry after you jump. Live calls and live sports keep only a tiny buffer, because the future hasn't happened yet, so they react to wobbles straight away.
See it in action
- BonusWhy does a video go blurry, then sharp?You press play and the picture is smudgy for a second, then it snaps sharp.8 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 internet slow down in the evening?Picture the internet as water: your house's pipe, one shared pipe under the street and a big main from far away.9 min · interactive
Do it for real
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